Anchoring delivery system and methods

ABSTRACT

An anchoring delivery system for use in an intracranial artery is provided including a tethering device having an elongated tether and an anchor coupled to a distal end of the tether. The anchor is deployable from a low profile configuration to a higher profile configuration to fix the distal end of the tether at an anchoring site in an anchoring vessel. The tethering device is configured to be used with a guide-sheath having a lumen configured to receive the tether. Related devices, systems, and methods are also described.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to U.S. Provisional Application Nos.62/196,613, filed Jul. 24, 2015, entitled “Anchoring Guide System,” and62/275,939, filed Jan. 7, 2016, entitled “Anchoring Delivery system,”and 62/301,857, filed Mar. 1, 2016, entitled “Anchoring DeliverySystem,” the entire contents of which are hereby incorporated byreference herein in their entireties.

FIELD

The present technology relates generally to medical devices and methods,and more particularly, to delivery systems and methods for deliveringmedical devices to a target anatomy.

BACKGROUND INFORMATION

Acute ischemic stroke (AIS) usually occurs when an artery to the brainis occluded, preventing delivery of fresh oxygenated blood from theheart and lungs to the brain. These occlusions are typically caused by athrombus or an embolus lodging in the artery and blocking the arterythat feeds a territory of brain tissue. If an artery is blocked,ischemia follows, and brain cells may stop working. Furthermore, if theartery remains blocked for more than a few minutes, the brain cells maydie, leading to permanent neurological deficit or death. Therefore,immediate treatment is critical.

Two principal therapies are employed for treating ischemic stroke:thrombolytic therapy and endovascular treatment. The most commontreatment used to reestablish flow or re-perfuse the stroke territory isthe use of intravenous (IV) thrombolytic therapy. The timeframe to enactthrombolytic therapy is within 3 hours of symptom onset for IV infusion(4.5 hours in selected patients) or within 6 hours for site-directedintra-arterial infusion. Instituting therapy at later times has noproven benefit and may expose the patient to greater risk of bleedingdue to the thrombolytic effect. Endovascular treatment most commonlyuses a set of tools to mechanically remove the embolus, with our withoutthe use of thrombolytic therapy.

The gamut of endovascular treatments include mechanical embolectomy,which utilizes a retrievable structure, e.g., a coil-tipped retrievablestent (also known as a “Stentriever”), a woven wire stent, or a lasercut stent with struts that can be opened within a clot in the cerebralanatomy to engage the clot with the stent struts, create a channel inthe emboli to restore a certain amount of blood flow, and tosubsequently retrieve the retrievable structure by pulling it out of theanatomy, along with aspiration techniques. Other endovascular techniquesto mechanically remove AIS-associated embolus include Manual AspirationThrombectomy (MAT) (also known as the “ADAPT” technique). MAT is anendovascular procedure where large bore catheters are inserted throughthe transfemoral artery and maneuvered through complex anatomy to thelevel of the embolus, which may be in the extracranial carotids,vertebral arteries, or intracranial arteries. Aspiration techniques maybe used to remove the embolus through the large bore catheters. Anotherendovascular procedure is Stentriever-Mediated Manual AspirationThrombectomy (SMAT) (similar to the Stentriever-assisted “Solumbra”technique). SMAT, like MAT, involves accessing the embolus through thetransfemoral artery. After access is achieved, however, a retrievablestructure is utilized to pull the embolus back into a large borecatheter.

SUMMARY

The endovascular treatments for AIS described above face the samechallenge: navigating complex anatomy leading to the cerebrovasculararea. The anatomy leading to the lesion can be tortuous and diseased,which may complicate device delivery. To access the cerebral anatomy,guide catheters or guide sheaths are used to direct interventionaldevices such as retrievable structures, guidewires, microcatheters, andintermediate access catheters to the target site from the access site,typically the femoral artery. It can often be very challenging toestablish guide or sheath position in a fashion that is stable andprovides support for device delivery. To maneuver the catheters intoposition, coaxial, triaxial, or quadraxial systems are often used inwhich a guidewire/microcatheter system is first deployed and coaxiallarger catheters are subsequently delivered. The clinical challenge,especially in the octogenarian population, is the elongation of theaortic arch against the fixed thoracic descending aorta, leading to ashifting of all great vessels, especially the brachiocephalic takeoff.Such shifting makes it more challenging to access the anatomy duringtreatment of, e.g., stroke, aneurysm, and other distally locatedvascular diseases. As catheters, wires, balloons, stents, or retrievablestructures are advanced through the great vessels, they have a tendencyto prolapse into the ascending aorta when pushed into a highly angulatedand/or tortuous anatomy.

It would be advantageous, and even necessary in cases where it might beimpossible to advance a catheter deep into the vasculature, to providean anchoring delivery system to provide support during endovasculartreatment of AIS (or during any other procedures employing theadvancement of sheaths or catheters). For example, an anchoring deliverysystem may be beneficial during vascular procedures like the treatmentof chronic total occlusions during coronary intervention. Essentially,any tortuous or complex target anatomy may be more easily accessed withthe benefit of increased stabilization of a medical device beingdelivered to the target site.

It should be apparent from the foregoing that there is a need to providesystems and methods for providing an anchoring delivery system forprocedures that include the advancement of catheters and sheaths into atarget anatomy like, but not limited to, AIS procedures.

In a first implementation, an anchoring delivery system for use in anintracranial artery is describing. The system includes a tetheringdevice having an elongated tether and an anchor coupled to a distal endof the tether. The anchor is deployable from a low profile configurationto a higher profile configuration to fix the distal end of the tether atan anchoring site in an anchoring vessel. The tethering device isconfigured to be used with a guide-sheath having a lumen configured toreceive the tether.

The anchoring delivery system can further include the guide-sheath. Thelumen of the guide-sheath can be a working lumen configured to deliverat least one working device into a target vessel. The lumen of theguide-sheath can be a tether lumen separate from the working lumen. Theguide-sheath can be reversibly attachable to the tether at a point offixation proximal to the anchoring site. The anchor can be deployed atthe anchoring site and the guide-sheath can be attached to the tether atthe point of fixation. The tether between the anchoring site and thepoint of fixation can be tensioned, for example, upon delivery of aworking device. One or both of the tethering device and the guide-sheathcan include a tether gripper at the point of fixation to attach theguide-sheath to the tether of the tethering device. The tether lumen canextend from a tether port near a distal end of the guide-sheath to thetether gripper. The working lumen can extend from a mouth at or near thedistal end of the guide-sheath to a proximal end of the guide-sheath.The guide-sheath can include a deflecting surface between the workinglumen and the tether lumen. The deflecting surface can be oblique to theworking lumen.

The anchor in the higher profile configuration can engage an anchoringanatomy and resist a proximal pull on the tether. The tether can be anelongated member extending from a proximal end to a distal joint thatattaches to the anchor. The distal joint can removably attach the tetherto the anchor. The distal joint can fixedly attach the tether to theanchor. The tether can have a cross-sectional diameter that varies alonga length of the tether. The anchor can automatically self-expand fromthe low profile configuration to a higher profile configuration when theanchor is unconstrained. The anchor need not automatically self-expandfrom the low profile configuration to a higher profile configurationwhen the anchor is unconstrained. The tether can include an anchor wireextending through a runner tube such that a withdrawal load applied tothe anchor wire causes the anchor wire to move relative to the runnertube and the anchor to transition to the low profile configuration. Theanchor can include several convoluted struts. The anchor can be a coiledwire. The anchor can be a curved wire.

The system can further include a pusher tube slidably positioned overthe tether. The pusher tube can be gripped and advanced to push theanchor forward for delivery to an anchoring site in a target anatomy.The system can further include a delivery element positioned over theanchor to collapse or constrain the anchor in the low profile state. Theanchoring device can lock to at least a portion of the guide-sheath. Thetether can be a flexible wire, rod, ribbon, or hypotube. The tether andthe anchor can be formed from a single and same wire. The tether and theanchor can be formed from separate wires.

The tether can include an outer running tube positioned over an inneranchor wire, the inner anchor wire being attached at a distal end to theanchor. The inner anchor wire and outer running tube can be slidablypositioned relative to one another. A first locking element can beattached to a proximal end of the anchor wire and a second lockingelement can be attached to a proximal end of the runner tube. The firstlocking element and second locking element can be actuated relative toone another to transition the anchor between the low profileconfiguration and the higher profile configuration.

The system can further include the guide-sheath having an elongated bodyextending from a proximal furcation at a proximal end region to a distaltip at a distal end. The distal tip can be configured to bluntly dissectthrough and dilate narrowed sections of a diseased vessel. The elongatedbody of the guide-sheath can include a tether lumen and a working lumen.A segment of the tether lumen can bifurcate away from a segment of theworking lumen. The distal tip of the guide-sheath can have a same orsimilar outer diameter as a section of the body of the guide-sheathleading up to the distal tip. The distal tip can have a distal faceorthogonal to a longitudinal axis passing through the body of theguide-sheath. The distal tip can be an elongated tubular portionextending distal to a region of the body having a uniform outer diametersuch that the elongated tubular portion has a reduced diameter comparedto the uniform outer diameter of the body. The tether lumen can have adistal end. The tether lumen can form a tether entry port in a distalface of the guide-sheath and the working lumen can have a distal endforming a working port in the distal face. The tether lumen can form atether entry port along a side of at least a distal region of the body.The guide-sheath can include a distal tip that tapers from a section ofthe body leading up to the distal end. An outer surface of the body ofthe guide-sheath can have a diameter that reduces from a largerdimension to a smaller dimension at a distal end of the tether lumen.The distal tip can taper from an outer diameter of approximately 0.114″to about 0.035″. The distal tip can taper from 0.110″ to 0.035″ over alength of approximately 50 mm. The tip can be concentrically disposedaround a tether port formed by the tether lumen. The working lumen canextend parallel to the tether lumen through the body to a mouth locatedproximal to a tether port near the distal end of the guide-sheath. Theworking port can be an elongated mouth disposed in a side surface of thebody. The mouth can have a dimension in at least one direction that islarger than a diameter of the working lumen. The tether lumen can formmultiple tether ports in a distal region of the guide-sheath. Theworking lumen can extend along a deflecting surface that directs aworking device passing distally through the body of the guide-sheathoutward through a mouth and a distal region of the guide-sheath. Thedeflecting surface can be oblique to the working lumen. The tether lumencan have a diameter large enough to receive the tether, but not largeenough to receive the anchor of the tethering device. The tether lumencan have a diameter large enough to receive the anchor over at least aportion of a length of the tether lumen. The guide-sheath can include achamber located proximal to tether entry port in the distal tip of theguide-sheath. The chamber can be sized to receive the anchor of thetethering device.

The systems described herein can further include at least one workingdevice that fits through a working lumen of the guide sheath. Theworking device can be a catheter system. The catheter system can includea catheter having a flexible distal luminal portion having a proximalend, a proximal end region, a distal end, and a lumen extending betweenthe proximal end and the distal end. The catheter can include a proximalspine extending proximally from the proximal end region. The proximalspine can be less flexible than the distal luminal portion and isconfigured to control movement of the catheter. The catheter system canfurther include a catheter advancement element. The catheter advancementelement can include a flexible elongate body having a proximal endregion, a distal tip, a single lumen that terminates at a distal openingin fluid communication with the vessel, and an outer diameter. The outerdiameter can be sized to be received within the lumen of the luminalportion of the catheter. The single lumen can extend longitudinallythrough the elongate body to the distal opening and can be sized toaccommodate a guidewire therethrough. The catheter advancement elementcan include a proximal portion extending from the proximal end region ofthe elongate body and extending proximally outside of the vessel of thepatient. The proximal portion can have a single lumen that communicateswith the single lumen of the flexible elongate body. The catheter can besized to fit within the working lumen.

In an interrelated aspect, described herein is an anchoring deliverysystem. The system includes a tethering device having an elongatedtether and an anchor coupled to a distal end of the tether. The anchoris deployable from a low profile configuration to a higher profileconfiguration to fix the distal end of the tether at an anchoring sitein an anchoring vessel. The tethering device is configured to be usedwith a guide-sheath having a lumen configured to receive the tether. Theanchoring delivery system includes the guide-sheath. The lumen of theguide-sheath is a working lumen configured to deliver a working deviceinto a target vessel.

The guide sheath can include a working lumen and a tether lumen. Thesystem can further include a working device that fits through theworking lumen. When the anchor is deployed at the anchoring site and theguide-sheath is attached to the tether at the point of fixation, thetether between the anchoring site and the point of fixation istensioned, for example, upon delivery of the working device. One or bothof the tethering device and the guide-sheath can include a tethergripper at the point of fixation to attach the guide-sheath to thetether of the tethering device.

In an interrelated aspect, disclosed is an anchoring delivery systemhaving a tethering device and a guide-sheath. The tethering device hasan elongated tether and an anchor coupled to a distal end of the tether.The anchor is deployable from a low profile configuration to a higherprofile configuration to fix the distal end of the tether at ananchoring site in an anchoring vessel. The tethering device isconfigured to be used with the guide-sheath having a lumen configured toreceive the tether. The lumen of the guide-sheath is a working lumenconfigured to deliver at least one working device into a target vessel.When the anchor is deployed at the anchoring site and the guide-sheathis attached to the tether at the point of fixation. The tether istensioned between the anchoring site and the point of fixation, forexample, upon delivery of a working device.

In an interrelated aspect, described is an anchoring delivery system foruse in an intracranial artery having a tethering device, a guide-sheath,and at least one working device. The tethering device has an elongatedtether and an anchor coupled to a distal end of the tether. The anchoris deployable from a low profile configuration to a higher profileconfiguration to fix the distal end of the tether at an anchoring sitein an anchoring vessel. The tethering device is configured to be usedwith a guide-sheath having a lumen configured to receive the tether. Theguide-sheath has a working lumen configured to deliver a working deviceinto a target vessel. When the anchor is deployed at the anchoring siteand the guide-sheath is attached to the tether at the point of fixation.The tether is tensioned between the anchoring site and the point offixation, for example, upon delivery of a working device.

In an interrelated aspect, described is a method including delivering atethering device to an anchoring vessel. The tethering device includesan anchor coupled to a distal end of a tether. The method includesdeploying the anchor of the tethering device in the anchoring vessel.The method includes advancing a guide-sheath over the tether of thetethering device to position an opening from the guide-sheath near anentrance of a target vessel.

The method can further include attaching the guide-sheath to the tetherof the tethering device. The tethering device can fix and support theguide-sheath for advancing at least one working tool through theguide-sheath. The anchor can be deployed at an anchoring site in theanchoring vessel distal to the entrance of the target vessel. Theguide-sheath can include a tether lumen to receive the tether. Theguide-sheath can be attached to the tether by a tether gripper at apoint of fixation proximal to the entrance of the target vessel.

The method can include delivering at least one working device through aworking lumen of the guide-sheath into the entrance of the targetvessel. Delivering the working device can tension the tether between theanchoring site and the point of fixation. The tether lumen and theworking lumen can be the same lumen. The method can include advancing asecond tethering device through a working lumen of the guide-sheath intothe target vessel. The second tethering device can include a secondanchor coupled to a second distal end of a second tether. The method caninclude deploying the second anchor of the second tethering device inthe target vessel. The method can include removing the guide-sheath fromthe tether of the tethering device. The method can include advancing theguide-sheath over the second tether of the second tethering device toposition the opening from the guide-sheath near a second entrance of asecond target vessel. The method can include advancing the secondtethering device through the deployed anchor of the first tetheringdevice. The method can include advancing the guide-sheath over thetether to capture the anchor and removing the guide-sheath and thecaptured anchor from the target anatomy.

In an interrelated aspect, disclosed is a method including advancing acatheter over a guidewire into an anchoring vessel and exchanging theguidewire for a tethering device. The tethering device includes ananchor coupled to a distal end of a tether. The method includesdeploying the anchor of the tethering device in the anchoring vessel;advancing a guide-sheath over the catheter to position a mouth of theguide-sheath near an entrance of a target vessel; removing the catheterfrom the guide-sheath; and attaching the guide-sheath to the tether ofthe tethering device.

The anchor can be deployed at an anchoring site in the anchoring vesseldistal to the entrance of the target vessel. The guide-sheath caninclude a tether lumen to receive the catheter and the tether. Theguide-sheath can be attached to the tether by a tether gripper at apoint of fixation proximal to the entrance of the target vessel. Themethod can further include advancing a working device through a workinglumen of the guide-sheath into the entrance of the target vessel.Tensioning the tether between the anchoring site and the point offixation. The tether lumen and the working lumen can be the same lumen.

In some variations, one or more of the following can optionally beincluded in any feasible combination in the above methods, apparatus,devices, and systems. More details of the devices, systems, and methodsare set forth in the accompanying drawings and the description below.Other features and advantages will be apparent from the description anddrawings.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other aspects will now be described in detail with referenceto the following drawings. Generally speaking the figures are not toscale in absolute terms or comparatively, but are intended to beillustrative. Also, relative placement of features and elements may bemodified for the purpose of illustrative clarity.

FIG. 1A illustrates a perspective view of an anchoring delivery systemhaving a tethering device, a tetherable guide-sheath, and animplementation of a working device extending therethrough;

FIG. 1B illustrates an exploded view of the anchoring delivery systemand the working device of FIG. 1A;

FIG. 1C illustrates a detail view of a distal end of the tetherableguide-sheath of FIG. 1A taken along circle C-C;

FIG. 1D illustrates a detail view of a distal end of a catheteradvancement element shown in FIG. 1A taken along circle D-D;

FIG. 2A illustrates a perspective view of a tethering device, inaccordance with an implementation;

FIGS. 2B-2D illustrate detail views, taken from Detail A of FIG. 2A, ofan anchor coupled to a tether of a tethering device;

FIG. 3 illustrates a detail view of an anchor of a tethering device;

FIG. 4 illustrates a perspective view of a tethering device, inaccordance with an interrelated implementation;

FIG. 5A illustrates a detail view, taken from Detail A of FIG. 4, of adistal portion of a tethering device;

FIG. 5B illustrates a sectional view, taken about line A-A of FIG. 5A,of a distal portion of a tethering device;

FIG. 5C illustrates a detail view, taken from Detail A of FIG. 4, of adistal portion of a tethering device;

FIG. 5D illustrates a sectional view, taken about line A-A of FIG. 5C,of a distal portion of a tethering device;

FIG. 5E illustrates a detail view, taken from Detail A of FIG. 4, of adistal portion of a tethering device;

FIG. 5F illustrates a detail view, taken from Detail A of FIG. 4, of adistal portion of a tethering device;

FIG. 5G illustrates the tethering device of FIG. 5F after furtherexpansion of the anchor;

FIG. 5H illustrates a detail view, taken from Detail A of FIG. 4, of adistal portion of a tethering device, in accordance with an interrelatedimplementation;

FIG. 5I illustrates a detail view, taken from Detail A of FIG. 4, of adistal portion of a tethering device, in accordance with an interrelatedimplementation;

FIGS. 5J-5L illustrate detail views, taken from Detail A of FIG. 4, of adistal portion of a tethering device, in accordance with an interrelatedimplementation;

FIGS. 5M-5O illustrate schematic views of an anchoring vessel and ananchor;

FIGS. 5P-5R illustrate schematic views of a method of manufacturing ananchor of a tethering device, in accordance with an implementation;

FIGS. 5S-5U illustrate schematic views of further implementations of adistal portion of a tethering device, in accordance with an interrelatedimplementation;

FIGS. 6A-6B illustrate schematic views of a tethering device deployment,in accordance with an implementation;

FIGS. 7A-7B illustrate schematic views of a tethering device deployment,in accordance with an implementation;

FIG. 8A illustrates a schematic view of a tethering device in anunexpanded state, in accordance with an implementation;

FIG. 8B illustrates a schematic view of the tethering device of FIG. 8Ain an expanded state;

FIG. 8C illustrates a schematic view of the tethering device in anexpanded state of FIG. 8B and a locked state;

FIGS. 9A-9C illustrate schematic views of a tethering device deployment,in accordance with an implementation;

FIGS. 10A-10C illustrate schematic views of a tethering devicedeployment, in accordance with an implementation;

FIGS. 10D-10E illustrate schematic views of a further implementation ofa tethering device deployment, in accordance with an implementation;

FIG. 11 illustrates a perspective view of a tetherable guide-sheath, inaccordance with an implementation;

FIGS. 12A-12B illustrate detail views, taken from Detail B of FIG. 11,of a distal end of a tetherable guide-sheath;

FIGS. 12C-12D illustrate detail views, taken from Detail B of FIG. 11,of a distal end of a tetherable guide-sheath;

FIG. 13 illustrates a sectional view of a distal end of a tetherableguide-sheath, in accordance with an implementation;

FIG. 14 illustrates a sectional view, taken about line A-A of FIG. 12B,of a distal end of a tetherable guide-sheath;

FIG. 15A illustrates a perspective view of a tetherable guide-sheath, inaccordance with an implementation;

FIG. 15B illustrates a detailed sectional view, taken from Detail B ofFIG. 15A, of a distal portion of a tetherable guide-sheath, inaccordance with an implementation;

FIG. 15C illustrates a detailed sectional view, taken from Detail B ofFIG. 15A, of a distal portion of a tetherable guide-sheath, inaccordance with an implementation;

FIGS. 16A-16B illustrate sectional views of a tetherable guide-sheath,in accordance with an implementation;

FIG. 17A illustrates a support guide during retrieval of an anchoringstructure;

FIG. 17B illustrates the retrieved anchoring structure in a tip of thesupport guide of FIG. 17A;

FIG. 18 illustrates a distal end of an anchoring delivery system havinga tethering device in a tether lumen of a tetherable guide-sheath and aworking device in a working lumen of the tetherable guide-sheath, inaccordance with an implementation;

FIG. 19 illustrates a distal end of an anchoring delivery system havinga tethering device in a tether lumen of a tetherable guide-sheath and aworking device in a working lumen of the tetherable guide-sheath, inaccordance with an implementation;

FIG. 20 illustrates a distal end of an anchoring delivery system havinga tethering device and a working device in a same lumen of a tetherableguide-sheath, in accordance with an implementation;

FIG. 21 illustrates a perspective view of a tetherable guide-sheath, inaccordance with an implementation;

FIG. 22 illustrates a sectional view, taken about line B-B of FIG. 21,of a tetherable guide-sheath, in accordance with an implementation;

FIG. 23 illustrates a sectional view, taken about line C-C of FIG. 21,of a tetherable guide-sheath, in accordance with an implementation;

FIG. 24 illustrates a sectional view of a proximal end of the tetherlumen of a tetherable guide-sheath, in accordance with animplementation;

FIG. 25 illustrates a tether gripper of a tetherable guide-sheath, inaccordance with an implementation;

FIG. 26 illustrates a tether gripper of a tetherable guide-sheath, inaccordance with an implementation;

FIG. 27 illustrates a tether gripper of a tethering device, inaccordance with an implementation;

FIG. 28 illustrates a method of using an anchoring delivery system todeliver a working device, in accordance with an implementation;

FIGS. 29A-29F illustrate operations of a method of using an anchoringdelivery system to deliver a working device, in accordance with animplementation;

FIG. 30 illustrates a method of using an anchoring delivery system todeliver a working device, in accordance with an implementation;

FIGS. 31A-31D illustrate operations of a method of using an anchoringdelivery system to deliver a working device, in accordance with animplementation;

FIG. 32 illustrates a method of using several anchoring delivery systemsto gain access to a target vessel, in accordance with an implementation;

FIGS. 33A-33B illustrate operations of a method of using severalanchoring delivery systems to gain access to a target vessel, inaccordance with an implementation;

FIG. 34 illustrates a method of using several anchoring delivery systemsto gain access to a target vessel, in accordance with an implementation;

FIGS. 35A-35C illustrate operations of a method of using severalanchoring delivery systems to gain access to a target vessel, inaccordance with an implementation;

FIG. 36 illustrates a flowchart of a method of deploying an anchoringdelivery system, in accordance with an implementation;

FIG. 37A-37B illustrate schematic views of an anchoring delivery systemdeployed in a target anatomy, in accordance with an implementation;

FIG. 38 illustrates a schematic view of an anchoring delivery systemdeployed in a target anatomy, in accordance with an implementation;

FIG. 39A-39B illustrate detailed sectional views, taken from Detail B ofFIG. 9, of a distal portion of a tetherable guide-sheath, in accordancewith an implementation;

FIG. 40A-40B illustrate operations of a method of deploying an anchoringdelivery system deployed in a target anatomy, in accordance with animplementation;

FIG. 41 illustrates a flowchart of a method of deploying an anchoringdelivery system, in accordance with an implementation;

FIG. 42A-42D illustrate schematic views of an anchoring delivery systemdeployed in a target anatomy, in accordance with an implementation;

FIG. 43 illustrates a flowchart of a method of deploying and using ananchoring delivery system for aspiration thrombectomy through a cathetersystem, in accordance with an implementation;

FIG. 44 illustrates a flowchart of a method of using an anchoringdelivery system for aspiration thrombectomy through a nested cathetersystem, in accordance with an implementation; and

FIG. 45 illustrates an implementation of a nested catheter system, inaccordance with an implementation.

It should be appreciated that the drawings are for example only and arenot meant to be to scale. It is to be understood that devices describedherein may include features not necessarily depicted in each figure.

DETAILED DESCRIPTION

Described herein are anchoring delivery systems that include a tetheringdevice and a tetherable guide-sheath to support and guide devices to atarget anatomy, in particular tortuous anatomy of the cerebralvasculature. The tethering device may include an anchor to be placed inan anchoring anatomy, e.g., a carotid, subclavian or vertebral arterialcirculation, and the tetherable guide-sheath may be tethered to a tetherof the tethering device, the tether being attached to the anchor. Thus,the tether may constrain the tetherable guide-sheath, and a subsequentworking device may be delivered through a lumen of the tetherableguide-sheath without concomitant prolapse of the tetherable guide-sheathor the working device when the working device, e.g., an advancedcatheter, wire, balloon, and/or retrievable structure, is advanced to atarget anatomy, e.g., a distal neurovasculature. The stability providedby the constrained tetherable guide-sheath will allow some AISapproaches to be performed successfully, accurately and more safely whenthey otherwise could not be completed due to tortuosity or angulation atthe great vessels or at the intracranial vasculature. Additionally, theanchoring delivery system can be used empirically or as a reaction toencountering challenging anatomy when attempting to place a guidecatheter in the internal carotid artery (ICA) or common carotid artery(CCA) during AIS procedures. The anchoring delivery system hassingle-operator ease of use.

Referring now to the drawings, FIG. 1A illustrates a perspective view ofan anchoring delivery system 10 supporting the advancement of animplementation of a working device 802 therethrough. FIG. 1B illustratesan exploded view of the anchoring delivery system 10 and an explodedview of the working device 802 of FIG. 1A. The anchoring delivery system10 includes an implementation of a tethering device 100 and a tetherableguide-sheath 400 configured to receive and support the advancement ofthe working device 802 therethrough, each of which will be described inmore detail herein.

It should be appreciated that the configuration of the tethering device100 can vary as described elsewhere herein. The tethering device 100does not necessarily need to be used with the tetherable guide-sheath400 as described. It should be appreciated that the tethering device 100can be used with any of a variety of comparable commercially availableguide-sheath to form an anchoring delivery system 10. For example, thetethering devices described herein can be used with guiding sheathshaving an ID between 0.087″-0.089″ such as the Cook SHUTTLE 6 F (CookMedical, Inc., Bloomington, Ind.), Terumo DESTINATION 6 F (Terumo EuropeNV), Cordis VISTA BRITE TIP (Cordis Corp., Hialeah, Fla.), and PenumbraNEURON MAX 088 (Penumbra, Inc., Alameda, Calif.), or comparablecommercially available guiding sheath. Further, it should be appreciatedthat the working devices for advancing through the guiding sheath canvary and need not be limited to the implementation shown in the figures.The guiding sheath, whether the tetherable guide sheath 400 or anothercommercially-available guiding sheath, can be used to deliver any of avariety of working devices configured to provide thrombotic treatmentssuch as large-bore catheters, aspiration thrombectomy, advancedcatheters, wires, balloons, retrievable structures such as coil-tippedretrievable stents “Stentriever”. The working devices can includevarious embolectomy devices known in the art as well as those describedherein.

Tethering Devices

The anchoring delivery system 10 can include a tethering device 100.FIG. 2A shows a perspective view of a tethering device 100 in accordancewith an implementation. The tethering device 100 can include a distalanchor 102 coupled to a proximal tether 104, for example, by a distaland/or a proximal joint 108. The tether 104 can be an elongate elementextending proximally from the distal anchor 102 such as a filamentouselement having an outer diameter that is small and flexible enough tocurve through the tortuous vessels of the cerebral vasculature withoutkinking. Keeping the tether 104 to a small diameter also allows thediameter of a tethered guide-sheath sized to receive the tether 104 tobe as small as possible minimizing the access arteriotomy size. In atleast some implementations, the tether 104 has a relatively low“pushability” such that it is generally not useful for advancing theanchor 102 through the vasculature without the assistance of a deliverytool. However, upon application of a proximal pulling force on thetether 104, for example when the tethering device 100 is anchored in avessel by the anchor 102, the tether 104 is strong enough to maintainthe tethering device 100 in a tensioned or taut state, as will bedescribed in more detail below. The anchor 102 can have any of a varietyof configurations as will be described in more detail below. Generally,the anchor 102 has a first, low-profile (unexpanded or constrained)configuration such that the anchor 102 may be delivered to the anchoringanatomy. The anchor 102 also has a second, higher-profile (expanded orunconstrained) configuration after delivery to and deployment within thetarget location such that the anchor 102 anchors (itself and thetethering device 100) within the target anatomy. It should beappreciated that use of the terms “expanded” and “unexpanded” as usedherein refer generally to an overall shape or profile of the anchor 102that is, in the case of an “expanded” anchor, greater than the overallshape or profile of the anchor 102 during delivery to the target anatomyor, in the case of an “unexpanded” anchor, less than the overall shapeor profile of the anchor 102 during anchoring in the target anatomy,respectively. “Expanded” and “unexpanded” as used herein are notintended to require any particular type of change in profile of theanchor 102.

The anchor 102 can be deployable from the unexpanded state to theexpanded state to fix a distal end of the tether 104 at an anchoringsite in an anchoring vessel of a target anatomy, as described below.Thus, the anchor 102 may have enough radial strength in the expandedconfiguration to grip the anchoring anatomy and resist a proximal pullon the tether 104. The anchor 102 is generally configured to anchorwithin the anchoring vessel, as opposed to dilating a stenosis orscaffold the vessel such as with stents. However, it should beappreciated that the anchors 102 described herein can anchor in a mannerthat also dilates, scaffolds, embeds, and/or distorts the anchoringvessel within which the anchor 102 is anchored. The anchors 102described herein can also facilitate anchoring of the tethering device100 by other features that do not necessarily involve a change in shape,such as by externalizing a portion of the wire and/or incorporatingsuperficial magnetic features in order to clamp outside the body, aswill be described in more detail below.

Still with respect to FIG. 2A, the tether 104 of the tethering device100 can be an elongated member extending from a proximal end 106 of thetethering device 100 to a distal joint 108 and having an outer surfaceextending along a longitudinal axis. The tether 104 can be stifferand/or less prone to bending than the wires typically attached toretrievable structures, such as a Merci retriever or a Stentrieverdevice, such that upon anchoring of the distal anchor 102 into a vesselthe tether 104 can serve a supportive function to support a tetherableguide-sheath 400 against buckling or prolapse, which will be describedin more detail below. The tether 104 can also be formed by a combinationof elements providing the proper supportive function. The tether 104 canhave various dimensions and/or material configurations. The dimensionsand/or material configurations of the tether 104 can be selected toachieve a desired tensile strength, flexibility, and trackability. Insome implementations, a diameter of the tether 104 ranges from 0.005inches to 0.025 inches, e.g., 0.008 inches, or 0.009 inches, or 0.010inches, or 0.035 inches, depending on the degree of support that thetether 104 provides. The tether 104 can be a solid wire rod, a ribbon,or a hypotube of stainless steel or NiTi. In some implementations, thetether 104 can be a stainless steel rod, ribbon or hypotube. In otherimplementations, the tether 104 can be Drawn Filled Tubing (DFT) with aradiopaque core, such as an outer sheath of a composite to providestrength and a core material to provide superelasticity, conductivity,radiopacity, resiliency, etc. In some implementations, the tether 104can be DFT of Nickel titanium with a radiopaque core such as platinum ortantalum.

The tether 104 can have several different cross-sectional areas atlocations along its longitudinal axis between the proximal end 106 ofthe tether 104 to where it couples with the anchor 102. For example, aproximal section near the proximal end 106 of the tether 104 can have afirst cross-sectional diameter. The first cross-sectional diameter maybe sized, for example, to favor support over trackability. Similarly,the tether 104 can include a distal section distal to the proximalsection that has a different cross-sectional diameter compared to thefirst cross-sectional diameter. For example, the distal section caninclude a second cross-sectional diameter that is smaller than the firstcross-sectional diameter of the proximal section. As such, the distalsection of the tether 104 can be configured to favor trackability oversupport.

The anchor 102 of the tethering device 100 can be sized to engage arange of vessel diameters, i.e., covering the lumen diameters to providesolid apposition against target anchor 102 sites such as the proximalCCA, proximal and mid-subclavian, and the external carotid artery (ECA).For example, the anchor 102 of the tethering device 100 can engagearteries of about 1 mm inside diameter to arteries with 40 mm insidediameters. For AIS procedures, it may be more common to anchor inarteries ranging from 2 mm inside diameter to 10 mm inside diameter. Inother implementations, the anchor 102 of the tethering device 100 may besized to be able to engage smaller arteries such as side branches. Incomparison to conventional retrievable structures used in SMATprocedures, which are typically rather flimsy and unable to anchoragainst an artery wall, the anchors described herein are specificallydesigned to anchor within a target anatomy. For example, the anchorsdescribed herein can be sized to anchor within internal carotid artery(ICA), middle cerebral arteries at the M1 segment, Vertebral, Basilarvessels, or vessels generally larger than 3 mm. The anchors describedherein can also be sized to anchor within vessels in the insular segmentarteries at the M2 segment, P1 or vessels which are generally within the2 mm-3 mm range. The anchors described herein can also be sized toanchor within vessels that are at the M3 segment or within vessels thatare generally less than 2 mm.

The anchor 102 of the tethering device 100 can have any of a variety ofconfigurations as described herein. For example, the anchor 102 caninclude an expandable structure configured to self-expand upon releaseof a constraint and/or expand when a force is applied. In someimplementations (e.g., FIGS. 2B and 2D), the anchor 102 of the tetheringdevice 100 can include a self-expanding material, such as nitinol, toexpand to an understood diameter in the air and exert a controllable andconsistent radial outward pressure when expanded and constrained withina vessel. In an implementation, the anchor 102 can include a closed-cellstent like structure, e.g., made of self-expanding material like nitinolthat may be set to a desired shape, for example, by a heat set process.In other implementations, the anchor 102 of the tethering device 100 caninclude a non-self-expanding material (e.g., FIG. 2C) such that theanchor 102 expands when a force is applied.

The anchor 102 can be collapsed to a first configuration for deliveryinto the target vessel, expanded to a second configuration upondeployment in the target vessel and subsequently collapsed to or towardsthe first configuration for removal from the vessel. The anchor 102 ofthe tethering device 100 can collapse or be constrained to a smalldimension such that it can be delivered through the lumen of a deliverycatheter, e.g., a microcatheter or finder catheter as described below.In some implementations, the anchor 102 of the tethering device 100 canbe actively collapsed using one or more additional features orcomponents. The anchor 102 can additionally or optionally be malleablesuch that it can be pulled into the small dimension. The anchor 102 ofthe tethering device 100 can be deployed by unsleeving the anchor 102,e.g., advancing the anchor 102 from the lumen of the delivery catheter,retracting the delivery catheter to expose the anchor 102 from thelumen, or a combination or the two.

FIG. 2B is a detail view taken from Detail A of FIG. 2A of an anchor 102coupled to a tether 104 of a tethering device 100. As described above,the tether 104 can terminate at a distal joint 108 between the proximalend 106 and the anchor 102. The anchor 102 can be physically connectedor attached to the tether 104 by one or more joints. The joint 108 maybe a permanent attachment between the tether 104 and the anchor 102,such as a welding joint or other attachment joint. Alternatively, theanchor 102 can be detachably connected to the tether 104 at the joint108. For example, the tether 104 can terminate at the distal joint 108,and the distal joint 108 may be severable at the discretion of anoperator to decouple the anchor 102 from the tether 104. The decouplingbetween the anchor 102 and the tether 104 can be a permanent orreversible decoupling. For example, the distal joint 108 between thetether 104 and the anchor 102 may be an adhesive joint having apredetermined breaking stress, such that when sufficient pulling forceis applied to the tether 104, the distal joint 108 breaks to detach thetether 104 from the anchor 102. In another implementation, the distaljoint 108 can be a threaded joint. For example, the tether 104 caninclude an external thread at the distal joint 108 that engages with aninternal thread of a tube section located at a proximal end or a distaljoint 108 of the anchor 102. Thus, the operator can rotate the tether104 around the longitudinal axis of the tethering device 100 when theanchor 102 is anchored in the anchoring anatomy to unscrew the tether104 from the anchor 102. It should be appreciated that other mechanismsof detachment between the tether 104 and the anchor 102 are consideredherein. Detachment of the anchor 102 from the tether 104 can be usefulwhere re-sheathing of the anchor 102 by a delivery catheter or atetherable guide-sheath, which will be described in more detail below,is not possible or may cause rupture or damage to a vessel. Thus, theanchor 102 can be left behind in the vessel and the tether 104 may besafely removed from a patient.

As shown in FIG. 2B, the anchor 102 can include several convolutedstruts 202 extending from the distal joint 108 to respective distalstrut ends 204. The convoluted struts 202 can follow any path from thedistal joint 108 to the distal strut ends 204. In an implementation, theconvoluted struts 202 can extend in a generally longitudinal directionwhen the anchor 102 is in the unexpanded or constrained state, and theconvoluted struts 202 can expand to extend in a generally spiraldirection when the anchor 102 is in the expanded state. Thus, atransverse dimension of the convoluted struts 202 can be less in theunexpanded state than in the expanded state, and a longitudinal lengthof the convoluted struts 202 can be greater in the unexpanded,constrained state than in the expanded state. As shown in FIG. 2B, whenthe convoluted struts 202 expand together they can form a weavedstructure that can engage an inner surface of the anchoring vessel. Therespective proximal ends of the convoluted struts 202 can be attached tothe distal joint 108 and the distal strut ends 204 can be freelysuspended. More particularly, the distal strut ends 204 may not beattached to each other such that the struts 202 are individuallycantilevered from the distal joint 108. However, the distal strut ends204 can be coupled to each other, e.g., by being commonly connected to asecond joint of the anchor 102, for example as shown in FIG. 5A, whichwill be described in more detail below. The struts 202 can alsoincorporate one or more barbs or cleats to improve their anchoringstrength within the vessel and prevent slippage of the anchor 102 in aproximal direction, for example, upon a pulling force being appliedduring use.

FIG. 2C is a detail view taken from Detail A of FIG. 2A of an additionalimplementation of an anchor 102 coupled to a tether 104 of a tetheringdevice 100. The anchor 102 can include a balloon 206 having an outersurface containing an internal volume. The tether 104 can include atubular structure, such as a hypotube, extending from the proximal end106 to a distal joint 108. An inner lumen of the tether 104 can be influid communication with the internal volume of the balloon 206 throughan inflation port 208 formed in a sidewall of the tether 104 hypotube.To facilitate tracking of the anchor 102, the distal joint 108 of thetether 104 can be connected to a soft, distal tip 210. The distal tip210 can be a spiral wire coil or other configuration tip that isflexible and atraumatic to the anchoring anatomy.

FIG. 2D is a detail view taken from Detail A of FIG. 2A of an additionalimplementation of an anchor 102 coupled to a tether 104 of a tetheringdevice 100. The anchor 102 can include a self-expandable structurecapable of self-expanding from a first, collapsed state to a second,expanded state. The tether 104 can connect to the anchor 102 at a distaljoint 108 and an outer diameter of the anchor 102 can enlarge from thedistal joint 108 towards the distal-most terminus of the anchor 102.Thus, when the self-expandable structure is expanded, an outer dimensionof the structure from the distal joint 108 towards a distal-mostterminus of the anchor can gradually widen to a maximum dimension. Theself-expandable structure of the anchor 102 can include a sequence ofanchor rings 211 disposed longitudinally relative to each other. Theanchor rings 211 can be connected by one or more ring connectors 212,such that the anchor rings 211 transmit longitudinal force between eachother. The self-expandable structure can have an open cell or a closedcell configuration, as is known in the art, depending on the number ofring connectors 212 used between adjacent anchor rings 211.

As mentioned above, the anchor 102 may have enough radial strength inthe expanded configuration to grip the anchoring anatomy and resist aproximal pull on the tether 104. FIG. 3 is a detail view of animplementation of an anchor 102 of a tethering device 100 that includesone or more ribs or struts 302 making up the expandable anchor 102. Theconfiguration of the struts 302, for example, their orientation and/orhow they provide a shape to the anchor 102 as a whole, as well as byincorporating features such as barbs, hooks, cleats, surface textures,etc. can be designed such that they aid to resist longitudinal movementof the anchor 102 once engaged with the anchoring anatomy. For example,the struts 302 can be configured to resist being pulled proximally whenthe strut 302 is engaged with tissue. In some implementations, the strut302 can be specifically designed to resist proximal movement within theanchoring anatomy, but may still be pushed in a distal direction throughthe anchoring anatomy. Thus, the anchor 102 can provide directionallybiased resistance to movement within the anchoring anatomy. As shown inFIG. 3, the struts 302 can include respective strut surfaces 304, whichmay face generally outward relative to a longitudinal axis 306 passingthrough the tether 104. The struts 302 can be oriented, e.g., by designor shape setting, such that a strut plane 308 passing through the strut302 parallel to the strut surface 304 is directed at an angle α to thelongitudinal axis 306. This may be referred to as “fish scaling”. Moreparticularly, the struts 302 or the cells of the anchor 102 can bendoutward during deployment such that a longitudinal plane passing throughthe struts 302 becomes angled relative to the longitudinal direction.For example, the angle can be proximally directed such that the strut302 will tend to dig into a tissue at the anchoring anatomy when theanchor 102 is pulled proximally. Thus, the “fish-scaled” struts 302 canresist a proximal pull applied to the tether 104. By contrast, the angleof the strut plane 308 can allow the struts 302 to be pushed distallywithout the struts 302 digging into the tissue. Thus, the anchor 102 canbe configured to grip the anchoring anatomy in one direction (e.g.proximally) but not in another direction (e.g. distally). “Fish-scaling”in stent design is often deemed to be undesirable for certainindications. However, “fish-scaling” of the anchor 102 in this contextcan be beneficial.

In addition to shaping the anchor 102 as a whole in a manner thatfacilitates gripping of the anchoring anatomy by the struts 302 can beindividually modified to facilitate such gripping. For example, thestrut surface 304 can be ribbed or roughened, e.g., by bead blasting orchemical etching, to increase friction between the tissue at theanchoring anatomy and the anchor 102. In an implementation, rather thanroughening the strut surface 304 by a secondary manufacturing process,the strut surface 304 can be manufactured by a process that does notinclude a polishing process that is otherwise applied to the remainderof the anchor 102. For example, the anchor 102 may be electropolishedduring manufacturing, but strut surface 304 may be masked during theelectropolishing process to avoid smoothing the strut surface 304. Inanother implementation, surface treatments such as applying an adhesiveto the outer surface of the struts 302 (or any other structural featureof the anchor 102) can be used to permanently or temporarily bond theanchor 102 with the tissue at the anchoring anatomy. The adhesive can beactivated upon contact with the tissue such that it does not cause theanchor 102 to stick to an inner surface of the tetherable guide-sheathor another catheter, e.g., a finder catheter, that the tethering device100 is delivered through.

As mentioned above, the anchor 102 of the tethering device 100 can alsobe designed to enhance anchoring by providing traction due toincorporation of one or more features that protrude from the anchor 102to anchor to the surrounding anatomy. For example, the anchor 102 caninclude features having a predetermined shape and size, such as one ormore barbs or hooks that protrude from the sides of the anchor 102 toimbed into surrounding vascular tissue and grip the vessel when aproximal pull force is exerted on the tether 104. These grippingfeatures of the anchor 102, however, can be configured to collapse suchthat the anchor 102 can be removed from the vessel. In someimplementations, the features can be configured to yield and/orcollapsed when a distal tip of tetherable guide-sheath 400 is advancedover them, as will be described in more detail below. For example, thestruts 202 shown in FIG. 2B can incorporate one or more cleats or barbson their distal ends to improve their grip within the anatomy. Thecleats can protrude outward toward the vessel wall such that uponexpansion or release of the struts 202 from their constrainedconfiguration the pointed ends of the cleats engage with the vesselwall. The cleats can be configured to undergo flexure upon re-sheathingsuch that they can be removed from the anatomy. For example, the cleatsin the unconstrained configuration can bend outward such that theirpointed ends extend towards the vessel wall and/or bend back towards theproximal direction to improve engagement with the vessel wall, forexample, upon proximal pull force on the tethering device. Their pointedends can be urged away from the vessel wall during re-sheathing, forexample, such that they flex back in the distal direction upon distaladvancement of a sheath or tubular structure to once again constrain thestruts 202 in a low profile configuration.

It should be appreciated that reference to one implementation of ananchor as having a particular feature, such as a surface treatment,anchoring feature, cleat, barb, etc., may be incorporated into any ofthe various anchors described herein.

FIG. 4 shows a perspective view of another tethering device inaccordance with an implementation having an anchor 102 physicallyconnected to a tether 104 and further including a pusher tube 109. Thetether 104 can be attached to the anchor 102 at one or more joints 108,such as a first joint 108 distal to the anchor 102 and/or a second joint108 proximal to the anchor 102. The pusher tube 109 can slide distallyand proximally relative to the tether 104, and may be removed prior todelivery of a tetherable guide-sheath 400 over the tether 104. Thetether 104 and/or pusher tube 109 can be gripped and advanced to pushthe anchor 102 forward for delivery to an anchoring site in a targetanatomy. Similarly, the pusher tube 109 can be retracted over the tether104 to remove the pusher tube 109 from the target anatomy, while keepingthe anchor 102 and the tether 104 in place to receive a tetherableguide-sheath, as will be described in more detail below. In someimplementations, the anchor 102 is collapsed or constrained inside thepusher tube 109 and the pusher tube 109 is used to provide some heft andpushability such that the pusher tube 109 is used to advance anotherwise flexible wire of the tether 104, for example through amicrocatheter, finder catheter, or diagnostic catheter. The size of thepusher tube 109 can remain small enough such that a tetherableguide-sheath 400 can be thread onto it, as will be discussed in moredetail below.

Referring to FIG. 5A, a detail view, taken from Detail A of FIG. 4, of adistal portion of a tethering device is illustrated in accordance withan implementation. The anchor 102 can be configured to expand when aforce is applied. The anchor 102 can include a closed-cell stent likestructure, e.g., made of self-expanding material like nitinol. Theanchor 102 can include a slit tube structure, for example, a structurethat includes a tube made of a self-expanding material like nitinol, andhaving several longitudinal slits or slots that allow the tube to beexpanded from an unexpanded, tubular shape, to an expanded shape.Accordingly, the anchor 102 may be set to a desired shape, for example,by a heat set process. Alternatively, the anchor 102 can be formed fromspring steel, alloys, or even polymeric material. Furthermore, thetether 104 can include an anchor wire 111 extending through a runnertube 113. The anchor wire 111 can be seen in FIG. 5A although is hiddenbehind a middle rib 115 of the slit tube in FIG. 5D. The anchor wire 111can connect to the anchor 102 at the distal joint 108. Similarly, therunner tube 113 may be connected to the anchor 102 at the proximal joint108. Thus, a withdrawal or pulling load applied to the anchor wire 111can lead to compression of the anchor 102 between the distal joint 108and the proximal joint 108. The compression may cause outward bowing andexpansion of the ribs 115 of the anchor 102. Accordingly, when actuatedwithin an anchoring vessel, the anchor 102 may secure the tetheringdevice 100 within the target anatomy.

FIG. 5B is a sectional view of FIG. 5A taken about line A-A, of a distalportion of the tethering device 100 shown in FIG. 4. The anchor 102 canbe a self-expanding structure having one or more rib segments 115interconnected with one or more spreader segments 117. The anchor 102can also include a slit tube structure having one or more rib segments115 extending longitudinally between a proximal joint 108 and a distaljoint 108 as shown in FIGS. 5D-5G. Each rib segment 115 can have adistal end attached to the distal joint 108 and a proximal end attachedto a distal end of a corresponding spreader segment 117. Similarly, eachspreader segment 117 can have a proximal end connected to the proximaljoint 108 of the anchor 102. In an implementation, the proximal joint108 includes a tether collar 119, such as a band that is swaged, glued,or otherwise affixed to one or more of the anchor 102 or the runner tube113 of the tether 104.

Still with respect to FIGS. 5A-5B, the anchor wire 111 can include arigid member designed to transmit longitudinal force to the distal joint108. Thus, the anchor wire 111 can be fixed to the distal joint 108, andcan impart an expansion force to the anchor 102 when pulled. Moreparticularly, when a compressive load is applied to the anchor 102between the distal joint 108 and the tether collar 119, the rib segments115 may tend to bow outward, and the spreader segments 117 may maintaina lateral separation between the proximal ends of the rib segments 115and the anchor wire 111. Accordingly, the anchor 102 may expand from anunexpanded state, e.g. a tubular shape, to an expanded state, e.g. abulbous shape. The anchor wire 111 may have an outer diameter of 0.006inch, the runner tube 113 may have an outer diameter of 0.011 inch, andthe pusher tube 109 may have an outer diameter of 0.020 inch. The wallthicknesses of the runner tube 113 and the pusher tube 109 may beminimized for their respective materials, which may be a medicallyacceptable material such as nitinol or stainless steel.

FIG. 5C is a detail view of a distal portion of a tethering device. Aswith other implementations, the anchor 102 can be configured toself-expand and/or expand when a force is applied to it. The anchor 102can include a slit tube structure, for example a tube made of aself-expanding material like nitinol, and the tube can include severallongitudinal slits or slots that allow the tube to be expanded from anunexpanded, tubular shape, to an expanded shape as shown. Accordingly,the slit tube structure can be set to a desired shape, for example theillustrated expanded shape, by a heat set process. Alternatively theanchor can be formed from spring steel, alloys, or polymeric materialsas described elsewhere herein. The tether 104 can include an anchor wire111 (hidden behind a middle rib of the slit tube structure in FIG. 5C)extending through a runner tube 113. The anchor wire 111 can connect tothe anchor 102 at the distal joint 108. Similarly, the runner tube 113can connect to the anchor 102 at the proximal joint 108. Thus, awithdrawal or pulling load applied to the anchor wire 111 can lead tocompression of the anchor 102 between the distal joint 108 and theproximal joint 108. The compression can cause outward bowing andexpansion of the ribs 115 of the anchor 102. Accordingly, when actuatedwithin the anchoring vessel, the anchor 102 can secure the tetheringdevice 100 within the target anatomy.

FIG. 5D is a sectional view taken about line A-A of FIG. 5C of a distalportion of a tethering device. The anchor 102 can be a slit tubestructure having one or more rib segments extending longitudinallybetween the proximal joint 108 and the distal point 108. Each ribsegment 115 may have a distal end attached to the distal joint 108 and aproximal end attached to the proximal joint 108. In an implementation,the proximal joint 108 includes a tether collar 119, such as a band thatis swaged, glued, or otherwise affixed to one or more of the anchor 102or the runner tube 113 of the tether 104. The distal end of the anchor102 in any of the various implementations described herein can includean atraumatic distal tip 210 (see FIGS. 5C-5E).

FIG. 5E illustrates an interrelated implementation in which the anchor102 includes a braid or overlapping wire structure. The anchor 102 caninclude a braided mesh 120 made of self-expanding material such asnitinol such that the mesh structure can be set to a desired shape by,for example, a heat set process. As with other implementations, thetether 104 can include an anchor wire 111 extending through a runnertube 113 such that a withdrawal or pulling load applied to the anchorwire 111 can lead to compression of the anchor 102 between the distaljoint 108 and the proximal joint 108. The compression can cause outwardbowing and expansion of the braided mesh 120 to secure the tetheringdevice in the target anatomy.

The runner tube 113 can be large enough to provide a slip fit with theanchor wire 111, such that the anchor wire 111 is able to easily slidealong an entire length of the runner tube 113. Nonetheless, the runnertube 113 may be small enough to minimize a diameter of a tether lumen inthe tetherable guide-sheath 400, as will be described below. The runnertube 113 can be fixed to the proximal joint 108 of the anchor 102, andcan be longer than a distance between the anchoring site and an exitport in the tetherable guide-sheath, but shorter than an overall lengthof the anchor wire 111 and the anchor lengths. Accordingly, the anchorwire 111 can exit a proximal end of the runner tube 113. The runner tube113 can have a similar length to the pusher tube 109, or the runner tube113 can be shorter than the pusher tube 109, for example, to minimize anoverall length of the anchoring delivery system 10.

The pusher tube 109 can be large enough to provide a slip fit with therunner tube 113, such that the runner tube 113 is able to easily slidealong a length of the pusher tube 109. The pusher tube 109, however, maybe small enough to abut the tether collar 119 or a proximal end of theanchor 102. Accordingly, the pusher tube 109 can be pressed forward(and/or the anchor 102 withdrawn) such that a distal face of the pushertube 109 presses against the tether collar 119 (or proximal end of theanchor 102) to exert a forward load on the anchor 102. The pusher tube109 can be longer than an overall length of a delivery catheter, whichmay typically be 100 cm in length. Accordingly, the pusher tube 109 canbe grasped and pulled back after delivery of the anchor 102 to theanchoring site to remove the pusher tube 109 from the anchor 102, thetether 104 and the patient anatomy.

FIGS. 5F-5G illustrate a distal portion of an implementation of thetethering device 100. As previously described, a distal end of anelongated member such as the anchor wire 111 may be connected to adistal end of the anchor 102 at a distal joint 108. The connection canbe either permanent or temporary, e.g., like the transition describedabove. For example, the anchor wire 111 can be threaded into the distaljoint 108 of the anchor 102 such that it may be rotated to detach fromthe anchor 102. The anchor wire 111 can also be connected permanently tothe anchor 102 such as by soldering, welding, gluing, crimping or otherfasteners. The anchor 102 can be preloaded into a pusher tube 109 orconstricting sheath. The anchor 102 can be loaded during the procedureinto a catheter, which might have already been placed into thevasculature of a patient. The distal attachment point or joint 108between the anchor wire 111 allows the push force to be transmitted tothe distal portion of the anchor 102 such that the anchor 102 can be“pulled” into the pusher tube 109, which can significantly simplifyloading. When the anchor 102 is constricted by the pusher tube 109, oris inside a catheter, the distal end of the pusher tube 109 or thedistal end of the catheter can be positioned at the location where theanchor 102 is to be deployed. During deployment, the pusher tube 109 orthe catheter can remain stable and the anchor 102 can be pushed out,e.g. by applying a distal load to the runner tube 113. After the distalpart of the anchor 102 is in contact with an inner surface of theanchoring anatomy, the pusher tube 109 may be pulled back to allow theanchor 102 to expand into contact with the anchoring anatomy. In someimplementations, the anchor 102 has a closed cell structure and theanchoring structure will be constricted in its diameter as long as theanchor 102 is not fully released. This feature can significantlysimplify the release of the anchor 102 into the target anatomy.

As best shown in FIGS. 5F and 5G, the tethering device 100 can include astopper 122 attached to the anchor wire 111. The stopper 122 can limitan amount of expansion of the anchor 102. For example, when the anchorwire 111 is pulled back within the runner tube 113, the stopper 122 mayeventually contact a proximal end of the anchor 102 and/or the tethercollar 119, to prevent additional bowing of the rib segments 115. Atthat point, the anchor 102 can grip the anchoring vessel with sufficientfriction to resist being pulled proximally by the tether 104.Accordingly, the expansion of the anchor 102 may stop. A distancebetween the stopper 122 and the proximal end of the anchor 102 candefine the maximum expansion dimension of the anchor 102. Furthermore,the distance can correlate with a radial force applied to the anchoringanatomy by the anchor 102. Thus, the stopper 122 can be located to tunethe radial force and the corresponding fictional force applied to thetissue by the anchor 102. More particularly, the anchor 102 can beconfigured to apply sufficient frictional force to the tissue to resista pull force applied by an operator to the tether 104, or a reactionload applied to the tether 104 by a working device being advanced to atarget anatomy, as described below.

The anchors described herein are designed to stay fixed in a vessel whendeployed, but may slide through a catheter for delivery to the anchoringsite by pushing on the tether 104 and/or pusher tube 109 of the system.Additionally, the anchor 102 may be withdrawn into a capturing element,such as a tetherable guide-sheath 400, a micro catheter, etc., forremoval from the anatomy. Accordingly, pulling the anchor 102 into thecapturing element may retract and collapse the expandable structurerather than expand the expandable structure. Furthermore, the elongatedsection of the tethering device 100, i.e., the combination of the tether104 and the pusher tube 109, may be larger during delivery of the anchor102 to the anchoring site than after delivery. More particularly, afterdelivering the anchor 102, the pusher tube 109 may be removed from theanatomy to make the remaining portion of the elongated section, i.e.,the tether 104, as thin as possible such that the tetherableguide-sheath may be advanced over the tether 104 and fixed to the tether104 while maintaining a sufficiently large working lumen to advance aworking device through the tetherable guide-sheath to a target vessel.

The anchors described herein can include a structure configured toanchor within an anchoring vessel that relies upon apposition of aplurality of struts or rings with the underlying vessel. The anchorsdescribed herein can also include a structure configured to anchorwithin an anchoring vessel without relying upon apposition. For example,the anchors can incorporate a coiled wire having one or more loopsconfigured to be constrained to a straighter, low profile configurationduring delivery and upon release of the constraint take on a higherprofile configuration that is helical, spiral, twisted, bent, curved, ordouble-curved etc. such that the anchor anchors within the vessel, forexample, as shown in FIGS. 5H-5L, and as will be described in moredetail below.

FIG. 5H shows a detail view of a distal portion of a tethering device inaccordance with an implementation. The tethering device 100 can includean anchor 102 configured to deform or distort the vessel as opposed tovessel apposition devices, such as a stent-type anchor, which rely uponhigh radial force. Such anchors provide excellent holding force even ifdeployed in straight vessels. The anchor 102 provides simplicity inmanufacture, deliverability, anchoring even in relatively straightvessels, and speed of execution that is appealing from a clinicalstandpoint. The tethering device 100 can include an anchor 102 having ashape memory wire that passively changes (e.g. self-expands) from asmaller profile configuration to a larger profile configuration. Thetethering device 100 including the anchor 102 can be configured to beinserted into a vessel through a diagnostic catheter that accepts0.038-inch (0.97 mm) guide wires. As such, the anchor 102 may include awire segment, e.g., a segment of wire having a diameter of, e.g.,0.038-inch, that is formed from a shape memory wire, e.g., nitinol wire.The shape memory wire may be pre-formed into a heat set shape having oneor more primary and/or secondary curves, bends, coils, or turns. Theshape memory wire can include a heat set shape that includes, but is notlimited to, a J-shape, a hook-shape or other profile having one or morebends, curves, coils, etc. Furthermore, the shape memory wire may beelastically deflected into a substantially straightened or elongatedshape for delivery through a lumen of a catheter. Thus, the anchor 102may be delivered in the smaller profile configuration when the shapememory wire is straightened (as shown by dotted lines 125 in FIG. 5H),and the anchor 102 may change into the larger profile configuration whenthe wire returns towards the pre-set hook-shape 127 within the anchoringvessel. When the anchor 102 returns towards the resting shape inside thevessel, the vessel itself can undergo an amount of distortion and inturn engage the anatomy surrounding the vessel. Thus, the vesseldistortion and resistance provided by the anatomy adjacent the vesselcan contribute to the level of holding force provided by the anchor 102upon deployment in the anchoring vessel, as is described in more detailbelow.

FIG. 5I, a detail view of a distal portion of a tethering device, isshown in accordance with an implementation. As described above, thetethering device 100 having a self-expanding shape memory wire designmay include a preformed shape that incorporates one or more loops orcoils 126. More particularly, the anchor 102 can include a coil 126having one or more turns about an axis. For example, a longitudinalsegment 128 of the anchor 102 may be along the central axis and theturn(s) of the coil segment 126 may extend proximally from a distal endof the longitudinal segment 128 toward a proximal end of thelongitudinal segment 128. The proximal end of the longitudinal segment128 may, for example, be at the transition point 124 between the anchor102 and the anchor wire 111. The coil 126 can be a single loop, 1.5loop, or a 2 loop anchor 102. Each loop of the coil 126 can be a 6 mmloop.

The coil segment 126 may extend out of plane with a direction ofinsertion or in plane with a direction of insertion. FIGS. 5J-5L showanother implementation of an anchor 102 formed by an extension springconfigured to coil in plane with a direction of insertion. Thelongitudinal segment 128 of the anchor 102 can be along the central axisA. The coil(s) 126 can loop back toward a proximal end of thelongitudinal segment 128 and then back toward a distal end of thelongitudinal segment 128. Rather than the coil(s) 126 being about thecentral axis A, the coil(s) 126 can loop around an axis B that is at anangle to, such as perpendicular or orthogonal to, the central axis Aforming a pigtail type coil or spiral wire. The coils 126 in a restingstate, unconstrained by either a tubular element or vessel (i.e. in theair), can touch each other or align side-by-side (see FIG. 5K). Duringdelivery towards a vessel, the coils 126 are constrained in asubstantially straightened configuration, for example, within a tubulardelivery element. Withdrawal of the tubular delivery element in aproximal direction (arrow A in FIG. 5L), unsheathes the coils 126 anddeploys the anchor 102 in the vessel. When deployed within a vessel, thecoils 126 take on a helical, semi-helical, curved, or “wiggle” shapethat can distort the vessel and fix the anchor 102 to the deployedlocation. As described above, the return of the coils 126 towards thisshape following removal of a straightening constraint (e.g. lumen of afinder catheter through which the anchor 102 is delivered) can distortthe vessel from its natural path to a path that is dictated in part bythe shape the coils 126 take on upon unsheathing. For example, FIG. 5Millustrates an anchoring vessel 1904 following its natural path withinthe cerebral anatomy. FIG. 5N illustrates a tethering device 100deployed within the anchoring vessel 1904 where the anchor 102 of thetethering device 100 is a stent-like vessel apposition device. Theanchoring vessel 1904 generally maintains its natural path and anchoringis provided by the apposition of the anchor 102 against the vessel wallwith or without the presence of additional barbs or cleats or otherfeature to improve fixation of the anchor 102. FIG. 5O illustratesanother implementation of a tethering device 100 deployed within theanchoring vessel 1904. In this implementation, the anchor 102 takes on asubstantially helical shape within the anchoring vessel 1904, which inturn, causes the anchoring vessel 1904 to distort away from its naturalpath and instead follow the directional turns of the anchor 102. In thisimplementation, engagement between the distorted vessel 1904 and thetissues of the adjacent anatomy assist in the holding force provided bythe anchor 102. The distortion within the surrounding tissue allows theresistance of the surrounding tissue to these distortions to increasethe hold of the anchor 102 such that the anchor 102 now engages anentire “block” of tissue rather than just the vessel wall. The holdingforce provided can be sufficient to prevent the anchor 102 from beingdislodged from the anchoring vessel 1904 upon application of a pullingforce on the tether 104 in a proximal direction even when tightly drawnand coupled to the proximal end of the guiding sheath 400 such thatadvancement of a working device causes a downward pulling force on thesheath 400.

The wire composition and size, as well as the coil diameter, the numberof coils, and the amount of expected external force on the anchor 102can all be considered in the design of the anchor 102. FIG. 5K shows twocoil segments 126 to the anchor 102, however, the anchor 102 can includeone, two, three, four, five, six, or more coil segments 126. Thediameter of the coils 126 can vary depending on the vessel within whichthe anchor device is intended to be used. The diameter of the coils 126can affect the holding force as the smaller the coil loop, generally thestiffer the anchor.

The tethering device 100 can include the tether 104 extending proximallyfrom the anchor 102. In an implementation, the tether 104 may have asmaller diameter than the shape memory wire used to form the anchor 102.In some implementations, the tether 104 can be formed from a shapememory wire having a diameter between about 0.005-inch to about0.014-inch, e.g., 0.006-inch, 0.007 inch, 0.008 inch, or 0.009-inch upto 0.016-inch. In other implementations, the tether 104 can have adiameter from about 0.005 inches to 0.025 inches, e.g., 0.008 inches, or0.009 inches, or 0.010 inches, or 0.035 inches, depending on the degreeof support that the tether 104 provides. The tether 104 can be a solidwire rod, a ribbon, or a hypotube. In some implementations, the tether104 can be a stainless steel rod, ribbon or hypotube. In otherimplementations, the tether 104 can be Drawn Filled Tubing (DFT) with aradiopaque core, such as an outer sheath of a composite to providestrength and a core material to provide superelasticity, conductivity,radiopacity, resiliency, etc. In some implementations, the tether 104can be DFT of Nickel titanium with a radiopaque core such as platinum ortantalum.

The tether 104 may be integrally formed with the anchor 102, e.g., theanchor 102 and the tether 104 may be segments of a same wire.Alternatively, the anchor 102 and the tether 104 may be different wiresthat are connected at a transition point 124 via a mechanical, adhesive,or welded bond. In some implementations, the wire of the tether 104 isintegral with the wire of the anchor 102 and the anchor 102 created bycoiling over a mandrel and/or via grinding. For example, in someimplementations the anchor 102 can be formed by winding the wire arounda shaft such as a mandrel. The ends of the anchor 102 can be bent into adesired shape, whether that is straight or otherwise looped, hooked, orbent. The anchor 102 can be formed by cold winding or hot winding andthen hardened to relieve stress and allow resilience in the spring. Theanchor 102 can be formed by coiling a length of wire around a mandrel Min a first direction (arrow A in FIG. 5P) and doubling back around themandrel M in a second opposition direction (arrow B in FIG. 5Q) tocreate a first overlap section. More overlap sections can be created byonce again coiling the wire about the mandrel M in the first direction(arrow A in FIG. 5R) until a coil having a particular holding strengthis formed. More coils can be formed in the length of wire in a similarmanner until an anchor 102 is formed having the desired number of coilshaving a desired overall diameter and a desired holding force. Theanchor 102 can also be formed by grinding a round or flat wire using acoiling lathe to create single diameter coils or tapered coils. Theanchor 102 can be formed of a plurality of materials including a corewire and an external coil laser welded to the core wire. The anchor 102can be formed of stainless steel wire, nitinol wire, drawn filled tube(DFT) with a radiopaque core, hypotube.

One skilled in the art will appreciate that a shape memory wire may bepre-formed to have numerous larger profile configuration shapes. Forexample, the coil segment 126 of the anchor 102 may extend distally fromthe longitudinal segment 128 of the anchor 102 with turns havingincreasing diameters such that a conical coil shape is formed.Alternatively, the turn diameters may increase and decrease in alongitudinal direction of the coil segment 126 such that a barbellshaped coil segment is formed. Still further, the coil segments 126 mayeach have a diameter that are substantially the same and sized to engagethe vessel within which the anchor 102 is implanted upon release fromthe catheter lumen. Thus, the anchor 102 may include a shape memory wiresegment that may be deformed or deflected to the smaller profileconfiguration and then released into a heat set shape of the largerprofile configuration to create friction against a vessel wall. Thelarger profile configuration of the anchor 102 may be wider in atransverse dimension than the smaller profile, and thus, the anchor 102may press against a vessel wall to anchor the tethering device 100 whenit emerges from the lumen of the catheter.

FIGS. 5S-5U illustrate various implementations of a distal end of atethering device 100. The anchor 102 can include one or more shockabsorber regions 123 and one or more anchoring loop regions 129. FIG. 5Sillustrates an anchor 102 having a wire coiled into a distal shockabsorber region 123 adjacent a central anchoring loop region 129 whereasFIG. 5T illustrates a distal anchoring loop region 129 having a floppyJ-tip 131. FIG. 5U illustrates an anchor 102 having a wire coiled into adistal anchoring loop region 129 and a proximal anchoring loop region129 interspersed with a first shock absorber region 123 and a secondshock absorber region 123, thus creating two sets of anchoring loops 129and two sets of absorbent loops 123.

The anchor 102, with or without additional barbed or cleat elements, canembed within the wall of the vessel and optionally can cause the vesselwithin which it is deployed to undergo a degree of distortion,particularly if a proximal tugging force is applied on the tether 104.Thus, the friction between the anchor 102 and the vessel aids in theretention of the tethering device in the vessel as does the distortionof the vessel within which the tethering device is anchored, andoptionally engagement between barbs of the anchor and the vessel. Thevessel can deform into a single or double curve under the distortionforce of the anchors 102 described herein further improving theiranchoring function while maintaining flow through the anchor 102 withlittle disturbances due to the presence of the anchor 102. Thus, acombination of forces provides an anchoring function. The combination ofproficient anchoring for the delivery of large bore catheters andmaintenance of blood flow in and around the anchor are beneficial tosuccessful interventions within the neurovasculature and consistentaccess catheter delivery to the skull base

It should be appreciated that the anchor itself need not embed withinthe wall of the vessel due to a shape change upon deployment. In someimplementations, the anchor 102 is deployed in a more superficialanatomic location, such as within a facial artery, that allows forfixation of the anchor 102 from outside the body anatomy. For example,the tethering device 100 can include a proximal tether 104 and a distalanchor 102 deployed within a superficial vessel. The distal anchor 102can be fastened within the superficial vessel by magnetic attractionbetween the distal anchor 102, formed of a magnetic material such asstainless or incorporating magnetic elements, and one or more magnetsplaced on a skin surface near the superficial vessel, such as on thecheek or the neck near the ear. In other implementations, at least aportion of the anchor 102 can be externalized and clamped outside thebody.

It should be appreciated that various anchor implementations aredescribed herein and the term anchor is used generally herein to referto an element used for anchoring of the tethering device within a targetanatomy. Anchors can include any of a variety of configurations asdescribed herein including, but not limited to self-expanding ornon-self-expanding devices, braids, mesh, wires, stents, coils, or otherparticular implementation described herein. Any of a variety ofcombinations of features of the anchors are considered herein. Further,although a particular anchor implementation may be shown in a particularfigure for purposes of illustration, it is not intended to be limitingor to suggest that the anchor implementation shown would be the onlyanchor implementation useful for that particular feature.

The deployment of the various anchoring devices described herein willnow be described. It should be appreciated that the anchor shown in thefigure is represented in schematic for illustration purposes only torepresent a change from a low profile configuration to a higher profileconfiguration. The actual configuration of the anchor can vary asdescribed herein.

Referring to FIGS. 6A-6B, a schematic view of a tethering devicedeployment is illustrated in accordance with an implementation. Thetethering device 100 can include a distal anchor 102, a proximal tether104 having an inner anchor wire 111 and an outer runner tube 113. Whendeploying the tethering device 100, the operator may fix the runner tube113 in place and adjust the placement of the anchor 102 in the vessel.The anchor 102 can be expanded and the anchoring can be tested bypulling the anchor wire 111 relative to the runner tube 113 and thenfixing the two in relative position to each other (see FIG. 6B). Thetethering device 100 can be adjustable, for example, if there is slip oran “extreme” moment during the procedure extra anchoring can betransiently applied to the anchoring vessel and released when thedistension applied to the vessel is not desired. The expansion appliedby pulling the anchor wire 111 can be in addition to expansion providedby self-expansion of the anchor 102 to a preformed expanded shape, forexample as shown in FIGS. 2B-2D or FIGS. 5A-5B. If the runner tube 113and anchor wire 111 interaction provides some friction the expansion ofthe anchor 102 can be retained from the friction between the twosystems. It can provide anchoring that allows the deployment of thetetherable guide-sheath 400 over the tether 104, i.e., the runner tube113/anchor wire 111 combination, as will be described in more detailbelow.

Referring to FIG. 7A, a schematic view of a tethering device deploymentis illustrated in accordance with an implementation. Once tetherableguide-sheath 400 is positioned, another adjustment of the runner tube113 relative to the anchor wire 111 can be done, and then the anchorwire 111 can be locked in place relative to the tetherable guide-sheath400. Referring to FIG. 7B, a schematic view of a tethering devicedeployment is illustrated in accordance with an implementation. In animplementation, when the fixation point is applied to the anchor wire111, downward forces on the tetherable guide-sheath will transmitdirectly to the anchor wire 111 and in return will expand the anchor 102as the distal tip is pulled downward with downward force—furtheranchoring the system in response to downward force. It is expected thatduring the procedure, as long as the anchor wire 111 fixation relativeto the tetherable guide-sheath 400 is constant, the anchor 102 willexpand and anchor in accordance with the forces that are transmitteddownward on the tetherable guide-sheath 400. Increasing or decreasing“baseline anchoring” can be dialed into the system in accordance withoperator preferences and the needs of the procedure. The baselineanchoring may also be applied by self-expansion of the anchor 102 to apreformed expanded shape as shown in FIGS. 5D-5F.

Referring to FIG. 8A, a schematic view of a tethering device in anunexpanded state is illustrated in accordance with an implementation.Taking this to a more mechanical level, one or more locking elements 130may be used to “open and close” the anchor 102 at different diameters(and corresponding tensions against the vessel wall). The anchor 102 isshown in a low-profile configuration with the anchor 102 cut away sothat the anchor wire 111 traversing the entire length of the assembly isvisible within the anchor 102 and exiting the proximal end of the runnertube 113. Specialized locking elements 130 can be applied individuallyto the portions of the anchor wire 111 and the runner tube 113 that areexposed, e.g., that are situated outside of a patient anatomy and/or arotating hemostatic valve (RHV) coupled with the tetherableguide-sheath, as described below. For example, a first locking element130 a can be coupled to the anchor wire 111 and a second locking element130 b can be coupled to runner tube 113.

Referring to FIG. 8B, a schematic view of a tethering device in anexpanded state is illustrated in accordance with an implementation. Withtightened down locking elements 130 a, 130 b, the relationship of theanchor wire 111 to the runner tube 113 can be adjusted—either adjustedto tactile feedback or perhaps to fluoroscopic visualization of theexpansion and contraction of the anchor. Tension can be applied bypulling the two locking elements 130 a, 130 b apart to expand the anchor102. The reverse can be used to contract the anchor 102 and may even beheld contracted to withdraw the device into a catheter or sheath.

Referring to FIG. 8C, a schematic view of a tethering device in anexpanded state and locked state is illustrated in accordance with animplementation. Once the desired tension is applied to expand the anchor102 to a target dimension for anchoring at an anchoring site in ananchoring vessel, the anchor wire locking element 130 a can be advancedforward to abut a proximal end of the runner tube 113. Holding theanchor wire locking element 130 a firm against the runner tube 113 atthe anchor wire/runner tube transition and locking the anchor wirelocking element 130 a down at that position can lock the relationship ofthe anchor wire 111 and the runner tube 113 relative to each other (andlock the anchor 102 under a fixed tension). This is “locking open” theanchor 102. For added security, the runner tube locking element 130 bcan be loosened and advanced to the face of the RHV and/or thetetherable guide sheath, and locked down to prevent movement of therunner tube 113 relative to the RHV/tetherable guide-sheath assembly. Ifthe RHV being used is not “specialized” to hold the runner tube 113firmly, there can be a risk of slippage. If the runner tube 113 is of astainless steel or nitinol or hardened material, when the operatorencounters resistance on advancing interventional tools and anchoring iscalled for a downward force can be transmitted from the tetherableguide-sheath down the column of the tether 104, for example, formed bythe anchor wire 111 extending through the runner tube 113. A standardcommercial RHV can slip, and thus, a tether gripper such as aspecialized RHV may be used to reinforce the relationship of the tether104 relative to the sheath assembly and is described in more detailbelow (see FIGS. 25-27).

As described herein the tethering device can vary in its pushability,steerability, torque and opacity. Thus, in some implementations thetethering device 100 can have a relatively pushable tether 104 such thatthe tethering device 100 can be advanced through a guide catheter. Inother implementations, the tethering device has a tether 104 that isless pushable to advance and steer the anchor 102 into place. Thus, apusher tube 109 or other tubular element 135 configured to receive thetether 104 may be incorporated to aid in the delivery of the anchor 102to the target site through a catheter lumen. FIGS. 9A-9B illustrate aschematic view of a tethering device 100 having an anchor 102 configuredto be elastically deformed into a low profile configuration. In thelow-profile configuration, the coil segments 126 of the anchor 102coupled at a distal end region of the tether 104 are extended orsubstantially straightened into a smaller profile configuration such asthose shown by dotted lines in FIGS. 5H-5I such that the anchor 102 canbe positioned within a tubular element 135 (see FIG. 9A). A pusher tube109 can be positioned over the tether 104 and within the tubular element135 such that a distal end of the pusher tube 109 abuts a proximal endof the anchor 102 to aid in the delivery of the anchor 102 at the targetlocation. In order to release the anchor 102 into the higher-profileconfiguration, the tubular element 135 can be withdrawn in a proximaldirection (arrow A) and/or the pusher tube 109 advanced in a distaldirection (arrow B) urging at least a portion of the anchor 102 to exitthe tubular element 135 prior to unsheathing the anchor 102 from thetubular element 135 such that the anchor 102 emerges from the lumen ofthe tubular element 135 and self-expand or otherwise return to a largerprofile configuration to anchor within a vessel (see FIG. 9B). Thepusher tube 109 can have an outer diameter between that of the tether104 and the anchor 102, for example an outer diameter of 0.006-inch to0.038 inch, e.g. 0.021-inch. As described elsewhere herein, one or morelocking elements 130 can be coupled to the tether 104, the tubularelement 135, and/or a portion of the pusher tube 109 and situatedoutside of a patient anatomy and/or a rotating hemostatic valve (RHV)coupled with a proximal end of the tetherable guide-sheath. Further, asdescribed elsewhere herein, the anchor 102 can be re-sheathed such as byadvancing the tubular element 135 in a distal direction, pulling thetether 104 in a proximal direction, or both such that the anchor 102abuts a distal end of the tubular element 135 and gradually straightensas the anchor 102 is pulled into the tubular element 135 (FIG. 9C).

As described above, the anchor 102 can incorporate one or more struts202 having free, distal strut ends 204. As shown in FIGS. 10A-10C, thestrut ends 204 can form cleats 205 that protrude outwards upon expansionor release of the struts 202 form their constrained configuration suchthat the pointed ends 204 of the cleats 205 can engage with the vesselwall. The cleats 205 can undergo flexure upon sheathing and re-sheathingsuch that they can be removable from the vessel. FIG. 10A shows thestruts 202 in a constrained configuration such that the cleats 205 andtheir pointed ends 204 are contained within a tubular element 135. Uponretraction of the tubular element 135 in a proximal direction (arrow A)and/or extension of the struts 202 in a distal direction (arrow B), thestruts 202 and associate cleats 205 are released from constrainingforces (FIG. 10B). The struts 202 can flex in a direction away from thelongitudinal axis of the tubular element 135 and the associated cleats205 can flex or bend such that their pointed ends 204 extend towards thevessel wall. In some implementations, the cleats 205 upon release fromthe constraint of the tubular element 135 can take on a curved shapesuch that their pointed ends 204 are oriented in a direction back towarda proximal direction (see FIG. 10B). As such, the cleats 205 can allowfor distal movement within the vessel, but are prevented from movingproximally within the vessel due to the pointed ends 204 of the cleats205 snagging on the vessel wall. The pointed ends 204 of the cleats 205can be urged away from the vessel wall during re-sheathing, for exampleby advancing the tubular element 135 in a distal direction such that thepointed ends 204 of the cleats 205 flex back towards the longitudinalaxis and the struts 202 are constrained in the lower profileconfiguration within the tubular element 135 (see FIG. 10C). FIGS.10D-10E illustrate another implementation of cleats 205 that can springout upon withdrawal of or advancement from a tubular element 135.

Tetherable Guide-Sheath

Again with respect to FIGS. 1A-1B, the anchoring delivery system 10 caninclude a tethering device 100 and a tetherable guide-sheath 400 tosupport and guide working devices 802 to a target anatomy. It should beappreciated that although the tethering devices are described herein inthe context of implementations of tetherable guide-sheaths 400 that theymay be used with conventional sheaths to provide the fixation andsupport as described elsewhere herein. FIG. 11 shows a perspective viewof an implementation of a tetherable guide-sheath 400. The tetherableguide-sheath 400 can be an over-the-wire (OTW) type device and includean elongated body 402 extending from a proximal furcation 404 at aproximal end region 403 to a tip 406 at a distal end configured tobluntly dissect through and dilate narrowed sections of a diseasedvessel as it is advanced. The proximal furcation 404 may include severallumens molded into a connector body to connect to corresponding lumensof the body 402 of the tetherable guide-sheath 400. For example, thebody 402 and the proximal furcation 404 may include a respective tetherlumen 408 and a respective working lumen 410. The proximal furcation 404may also include additional lumens, e.g., an optional lumen 412, thatcan be connected to a corresponding lumen of the body 402 to serve apurpose other than receiving the tether 104 of the tethering device 100or receiving a working device 802 to be delivered to a target anatomy.For example, the optional lumen 412 may be connected with a syringe todeliver contrast through a contrast lumen in the body 402 toward the tip406 and into the target anatomy. A segment of the tether lumen 408 canbifurcate away from a segment of the working lumen 410. Moreparticularly, the segment of the tether lumen 408 may extend at an anglefrom the segment of the working lumen 410 to create a separation betweenthe tether proximal port 414 and the working proximal port 416. Thetether lumen 408 can extend from the tether distal port 504 at a distalend to a tether proximal port 414 of the proximal portion 403 of theelongated body 402. Similarly, the working lumen 410 can extend from adistal end to a working proximal port 416 of the proximal portion 403 ofthe elongated body 402.

The furcation 404 can be coupled to a rotating hemostatic valve (RHV)434. As mention above, the furcation 404 can include an optional lumen412 that may be connected with a syringe via a connector 432 to delivera forward drip, a flush line for contrast or saline injections through alumen in the body 402 toward the tip 406 and into the target anatomy.The optional lumen 412 can also connect to a large-bore aspiration lineand an aspiration source (not shown) such as a syringe or pump to drawsuction through the working lumen 410. The furcation 404 can beconstructed of thick-walled polymer tubing or reinforced polymer tubing.The RHV 434 allows for the introduction of devices through theguide-sheath 400 into the vasculature, while preventing or minimizingblood loss and preventing air introduction into the guide-sheath 400.The RHV 434 can include a flush line or connection to a flush line sothat the guide-sheath 400 can be flushed with saline or radiopaquecontrast during a procedure. The flush line can also be used as a secondpoint of aspiration. The RHV 434 can be integral to the guide-sheath 400or the guide-sheath 400 can terminate on a proximal end in a female Lueradaptor to which a separate hemostasis valve component, such as apassive seal valve, a Tuohy-Borst valve or rotating hemostasis valve maybe attached. The valve 434 can have an adjustable opening that is openlarge enough to allow removal of devices that have adherent clot on thetip without causing the clot to dislodge at the valve 434 duringremoval. Alternately, the valve 434 can be removable and is removed whena device is being removed from the sheath 400 to prevent clotdislodgement at the valve 434. The furcation 404 can include variousfeatures of the proximal components described, for example, in U.S.application Ser. No. 15/015,799, filed Feb. 4, 2016, which isincorporated herein in its entirety. The systems described herein canprovide advantages from a user-standpoint over tri-axial systems in thatthey can be safely used by a single user. Common tri-axial systems havemultiple RHV—one for each component inserted. The positional location ofthe various components on the table, from left to right, inform users ofwhich component it is. For example, components positioned to a rightside of the table are inserted more distally and components positionedto the left side of the operating table are inserted more proximally.The space on the table must be quite large (e.g. up to 210 cm-220 cmlong). Generally all the components are arranged in this way and requirean additional technician to organize and arrange the various components.The systems described herein incorporate components inserted through asingle RHV. As such, rather than relying on a positional organizationspread out across a table over 6 feet long, multiple components of thesystems described herein extend through the same RHV such that a singleuser can control delivery, all the components can be shorter, and can beused with less risk of sterile field contamination.

The length of the elongated body 402 is configured to allow the distaltip 406 of the body 402 to be positioned as far distal as thebifurcation between the external carotid artery (ECA) and the internalcarotid artery (ICA), for example, from a transfemoral approach withadditional length providing for adjustments if needed. In someimplementations, the length of the body 402 can be in the range of 80 to90 cm or up to about 100 cm or up to about 105 cm. In implementations,the body 402 length is suitable for a transcarotid approach to thebifurcation of the carotid artery, in the range of 20-25 cm. In furtherimplementations, the body 402 length is suitable for a transcarotidapproach to the CCA or proximal ICA, in the range of 10-15 cm. The body402 is configured to assume and navigate the bends of the vasculaturewithout kinking, collapsing, or causing vascular trauma, even, forexample, when subjected to high aspiration forces.

Referring to FIG. 12A, a detail view, taken from Detail B of FIG. 11, ofa distal end of a tetherable guide-sheath is illustrated in accordancewith an implementation. The tip 406 of the tetherable guide-sheath 400can have a same or similar outer diameter as a section of the body 402leading up to the distal end. Accordingly, the tip 406 may have a distalface 502 orthogonal to a longitudinal axis passing through the body 402and the distal face 502 may have an outer diameter substantially equalto a cross-sectional outer dimension of the body 402. In animplementation, the tip 406 includes a chamfer, fillet, or taper, makingthe distal face 502 diameter slightly less than the cross-sectionaldimension of the body 402. In a further implementation, the tip 406 maybe an elongated tubular portion extending distal to a region of the body402 having a uniform outer diameter such that the elongated tubularportion has a reduced diameter compared to the uniform outer diameter ofthe body 402 (see FIGS. 12C-12D). Thus, the tip 406 can be elongated orcan be more bluntly shaped. Accordingly, the tip 406 may be configuredto smoothly track through a vasculature and/or to dilate vascularrestrictions as it tracks through the vasculature. In an implementation,the tether lumen 408 may have a distal end forming a tether distal port504 in the distal face 502. Similarly, the working lumen 410 may have adistal end forming a working port 506 in the distal face 502. As will bedescribed below, the tetherable guide-sheath 400 may also include one ormore tether entry ports 504 along a side of the body 402.

Referring to FIG. 12B, a detail view, taken from Detail B of FIG. 11, ofa distal end of a tetherable guide-sheath is illustrated in accordancewith an implementation. The tetherable guide-sheath 400 may include atip 406 that tapers from a section of the body 402 leading up to thedistal end. That is, an outer surface of the body 402 may have adiameter that reduces from a larger dimension to a smaller dimension ata distal end of the tether lumen 408, i.e., at the tether distal port504. For example, the tip 406 can taper from an outer diameter ofapproximately 0.114″ to about 0.035″. The angle of the taper of the tip406 can vary depending on the length of the tapered tip 406. Forexample, in some implementations, the tip 406 tapers from 0.110″ to0.035″ over a length of approximately 50 mm. In an implementation, thetether distal port 504 is centered along a longitudinal axis passingthrough the body 402. Thus, the tapered tip 406 may be concentricallydisposed around the tether distal port 504. Accordingly, the tapered tip406 may track smoothly around bends within the targeted anatomy to avoidcausing trauma to the tissue. The working lumen 410 may extend parallelto the tether lumen 408 through the body 402 to a mouth 508 locatedproximal to the tether distal port 504 near the distal end of thetetherable guide-sheath 400. More particularly, the working port 506 maybe an elongated mouth 508 disposed in a side surface of the body 402,for example proximal to the tip taper. The mouth 508 may be formed inthe side surface using manufacturing techniques such as skiving and/ordrilling. Thus, the mouth 508 may have a dimension in at least onedirection that is larger than a diameter of the working lumen 410. Forexample, the mouth 508 may have a longitudinal dimension that is largerthan a cross-sectional diameter of the working lumen 410. The diameterof the mouth 508 can be at least 1.5×, 2×, 2.5×, or 3× as large as anouter diameter of a working device 802 extending therethrough. The mouth508 can be skived such that it has a length from a proximal end to adistal end that allows for a working device 802 to exit at a range ofangles, for example, very nearly parallel to the body 402 to a positionthat is at an angle to the body 402, for example substantiallyperpendicular as well as greater than a right angle to the body 402.This arrangement allows for ease of delivery of a working device 802through the mouth 508 even in the presence of a severe angulation withinthe vessel being traversed or where a bifurcation is present. Often,tortuous segments in vessels and bifurcations have severe angulations to90° or greater angle up to 180°. Classic severe angulation points in thevasculature can include the aorto-iliac junction, the left subclavianartery takeoff from the aorta, the brachiocephalic (innominate) arterytakeoff from the ascending aorta as well as many other peripherallocations. A distal tip 406 can extend well beyond a distal end of themouth 508 such that the tip 406 forms an elongate, soft tip formaneuvering through the turns of the vasculature (see, e.g., FIGS.12C-12D). In some implementations, the mouth 508 can be located justproximal to the tip 406 or can be located at least 0.25 mm or more awayfrom the tip 406.

In an implementation, the tetherable guide-sheath 400 includes one ormore radiopaque markers 510. The radiopaque markers 510 can be disposednear the mouth 508. For example, a pair of radiopaque bands may beswaged, painted, embedded, or otherwise disposed in or on the body 402,for example on either side of the mouth 508. In some implementations,the radiopaque markers 510 include a barium polymer, tungsten polymerblend, tungsten-filled or platinum-filled marker that maintainsflexibility of the distal end of the device and improves transitionalong the length of the guide-sheath 400 and its resistance to kinking.In some implementations, the radiopaque marker 510 is a tungsten-loadedPEBAX or polyurethane that is heat welded to the body 402. The markers510 are shown in the figures as rings around a circumference of one ormore regions of the body 402. However, the markers 510 can have othershapes or create a variety of patterns that provide orientation to anoperator regarding the position of the mouth 508 within the vessel.Accordingly, an operator may visualize a location of the mouth 508 underfluoroscopy to confirm that the mouth 508 is directed toward a targetanatomy where a working device 802 is to be delivered. For example,radiopaque marker(s) 510 allow an operator to rotate the body 402 of thetetherable guide-sheath 400 at an anatomical access point, e.g., a groinof a patient, such that the mouth 508 provides access to an ICA bysubsequent working device(s), e.g., catheters and wires advanced to theICA. In some implementations, the radiopaque marker(s) 510 includeplatinum, gold, tantalum, tungsten or any other substance visible underan x-ray fluoroscope. In various implementations, the distance from thetether distal port 504 to the mouth 508 should be in a range thatfacilitates maneuvering of subsequent devices advanced through mouth508. It should be appreciated that any of the various components of thesystems described herein can incorporate radiopaque markers as describedabove.

Referring to FIG. 13, a sectional view of a distal end of a tetherableguide-sheath is illustrated in accordance with an implementation. In animplementation, the tetherable guide-sheath 400 includes the tip 406 atthe distal face 502 of the body 402. Thus, FIG. 13 may be across-sectional view of the distal end of the tetherable guide-sheath400 illustrated in FIG. 12A and described above. The working lumen 410and the tether lumen 408 can extend longitudinally along respective axesbetween the proximal end 403 of the tetherable guide-sheath 400 and thedistal tip 406. Furthermore, the tether lumen 408 may include more thanone tether distal port 504. For example, a tether distal port 504 mayoptionally be disposed in the distal face 502 of the body 402, and oneor more additional tether entry ports 504 may be disposed in a sidesurface of the body 402, such that the ports are in fluid communicationwith the tether lumen 408. More particularly, several tether entry ports504 may be disposed in the side surface at regularly spaced intervals.The tether 104 may be inserted through any of the tether entry ports 504into the tether lumen 408 to allow the tip 406 of the tetherableguide-sheath 400 to be advanced into a same or a different anatomy thanthe anatomy that the anchor 102 is deployed within. For example, thetether 104 may be disposed in an anchoring vessel and the tip 406 of thetetherable guide-sheath 400 may be advanced into a target vessel thatbifurcates away from the anchoring vessel. As such, it will berecognized that depending on the tether distal port 504 through whichthe tether 104 is placed, a different length of the tetherableguide-sheath 400 may be advanced into the target anatomy. For example,when the tether 104 is placed in the most distal tether distal port 504in the side surface, a distal segment of the tetherable guide-sheath 400between the utilized tether distal port 504 and the tip 406 may beadvanced into the target anatomy. When the tether 104 is placed in themost proximal port in the side surface, however, the distal segment ofthe tetherable guide-sheath 400 between the utilized tether distal port504 and the tip 406 may be longer. Accordingly, a stump tip of thetetherable guide-sheath 400 as that shown in FIG. 12A or a long tip ofthe tetherable guide-sheath 400 as shown in FIGS. 12C-12D may beadvanced into the target anatomy.

Referring to FIG. 14, a sectional view, taken about line A-A of FIG.12B, of a distal end of a tetherable guide-sheath is illustrated inaccordance with an implementation. In an implementation, the tetherableguide-sheath 400 includes the mouth 508 on a side surface of the body402. The working lumen 410 and the tether lumen 408 may extend in alongitudinal direction through at least a portion of the tetherableguide-sheath 400. For example, the working lumen 410 may extend along alongitudinal working axis 702 between the proximal furcation 404 and themouth 508. Similarly, a proximal tether lumen 704 having a segmentextending proximal to the mouth 508 may extend along a longitudinaltether axis 706 from the proximal furcation 404 (in the case of an OTWtetherable guide-sheath 400) and/or an exit port (in the case of arapid-exchange (RX) type of tetherable guide-sheath 400 as describedbelow). The lumens need not, however, extend longitudinally over theentire length of the tetherable guide-sheath 400. For example, a distaltether lumen 708 segment may be directed radially inward from theproximal tether lumen 704 over a portion of the tetherable guide-sheath400 distal to the mouth 508. More particularly, the tether lumen 408 maydiverge from the longitudinal direction toward the tether distal port504, which may be centrally located relative to a cross-section of thebody 402. Thus, the tether axis 706 passing through the tether distalport 504 may be radially offset from the tether axis 706 passing throughthe proximal tether lumen 704. The tether axis 706 passing through thetether distal port 504 may pass through the working lumen 410 at alocation proximal to the mouth 508, i.e., the tether distal port 504 maybe longitudinally aligned with the working lumen 410. In animplementation, the tether axis 706 passing through the tether distalport 504 may be coaxial with the working axis 702, or may be closer tothe working axis 702 then to the tether axis 706 extending through theproximal tether lumen 704.

In an implementation, the working lumen 410 extends along a deflectingsurface 710 that directs a working device 802 passing distally throughthe body 402 outward through the mouth 508. More particularly, theworking lumen 410 may extend from the mouth 508 at the tip 406 of thetetherable guide-sheath 400 to a proximal end 403 of the tetherableguide-sheath 400, and the tetherable guide-sheath 400 may include adeflecting surface 710 between the working lumen 410 and the tetherlumen 408. The deflecting surface 710 may be oblique to the workinglumen 410. That is, the deflecting surface 710 may include a ramp havinga radius that provides a smooth distal transition from the working axis702 to an exit axis extending radially outward through the mouth 508.The exit axis may be at an angle to the working axis 702, for example, a10, 15, 20, 25, 30, 35, 40, or 45 degree angle. In some implementationsthe exit axis is at a 30° angle.

As described above, the body 402 of the tetherable guide-sheath 400 mayinclude at least one lumen, and may include several lumens. Moreparticularly, the implementations depicted in FIGS. 12-14 are dual-lumencatheters having a working lumen 410 accompanied by a tether lumen 408along a majority of a length of tetherable guide-sheath 400. A diameterof tether lumen 408 may be less than a diameter of working lumen 410.Furthermore, the diameter of tether lumen 408 may vary. For example, thetether lumen 408 may have a diameter large enough to receive the tether104, but not large enough to receive the anchor 102 of the tetheringdevice 100. Alternatively, the tether lumen 408 may have a diameterlarge enough to receive the anchor 102 over at least a portion of alength of the tether lumen 408, e.g., to allow the anchor 102 to bepushed or pulled through the tether lumen 408. The tether lumen 408 mayalso have a diameter large enough to receive the anchor 102 when theanchor 102 is urged into a lower profile configuration such that it canbe received within at least a portion of the tether lumen 408.

According to some implementations, the tether lumen 408 is independentof the working lumen 410, and the working lumen 410 runs the entirelength of tetherable guide-sheath 400. In some implementations, thetetherable guide-sheath 400 will have performance characteristicssimilar to other sheaths used in carotid access and AIS procedures interms of kinkability, radiopacity, column strength, and flexibility. Theworking lumen 410 may deliver a working device toward the anchor 102,and the working device may be directed to the deflecting surface 710 tosmoothly exit at an angle to the longitudinal axis of the working lumen410. Furthermore, the mouth 508 of the tetherable guide-sheath 400 maybe wider than the internal diameter of the working lumen 410 so as toallow a wide range of exit angles of a working device exiting thetetherable guide-sheath 400. According to some implementations, theexiting working device can run almost parallel with the tetherableguide-sheath 400 to greater than 90 degrees, which severely angulatedarteries may require. Exit angles from the mouth 508 of the tetherableguide-sheath 400 should consider the variety of angles that the anatomymay require.

FIG. 15A illustrates a perspective view of an implementation of atetherable guide-sheath 400. As with other implementations, thetetherable guide-sheath 400 can include an elongated body 402 containingone or more lumens extending from a distal end to a proximal portion.For example, a tether lumen 408 may extend from a tether distal port 504at a tip 406 of the tetherable guide-sheath 400 to a tether proximalport 414 of the proximal portion 403. Similarly, a working lumen 410 mayextend from a mouth 508 of the tip 406 to a working proximal port 416 ofthe proximal portion 403. The tetherable guide-sheath 400 may include aproximal furcation 404 in the proximal portion 403 where a segment ofthe tether lumen 408 bifurcates away from a segment of the working lumen410. More particularly, the segment of the tether lumen 408 may extendat an angle from the segment of the working lumen 410 to create aseparation between the tether proximal port 414 and the working proximalport 416. One or more of the tether proximal port 414 or the workingproximal port 416 may incorporate a tether gripper 1502 (see FIGS.25-27).

Referring to FIG. 15B, a detailed sectional view taken from Detail B ofFIG. 15A, of a distal portion of a tetherable guide-sheath isillustrated in accordance with an implementation. In an implementation,the tetherable guide-sheath 400 may include a chamber 515 locatedproximal to the tether distal port 504 in the tip 406. The chamber 515may be sized to receive the anchor 102 of the tethering device 100. Forexample, the tether distal port 504 may be chamfered, i.e., having adistal port diameter that is larger than a proximal port diameter, suchthat the proximal joint 108 of the tethering device 100 moves smoothlyinto the tether distal port 504 when the tetherable guide-sheath 400 isadvanced over the anchor 102. The tether distal port 504 may expandslightly to receive the anchor 102. Furthermore, the anchor 102 may beretracted into the chamber 515 to store the anchor 102. Thus, in animplementation, the chamber 515 within the tip 406 of the tetherableguide-sheath 400 may have a chamber volume that is at least as large asa volume occupied by the anchor 102 when the anchor 102 is in theunexpanded, lower profile state. The chamber 515 may also have avariable chamber volume as described in more detail below with respectto FIGS. 17A-17B.

Referring to FIG. 15C, a detailed sectional view, taken from Detail B ofFIG. 15A, of a distal portion of a tetherable guide-sheath isillustrated in accordance with an implementation. In an implementation,the separation between the working lumen 410 and the tether lumen 408proximal to the mouth 508 may have a termination point distal to thetether gripper and/or the exit port of the tetherable guide-sheath 400.For example, the wall 517 dividing the working lumen 410 and the tetherlumen 408, which the ramp 710 makes up a portion of, may end proximal tothe mouth 508. This may allow the anchor 102 to remain separated from aworking device in the working lumen 410 in the distal region of thetetherable guide-sheath 400. However, separation between the tether 104and the working device at a location proximal to the mouth 508 may beless critical, and thus, the separating barrier or wall 517 mayterminate near this region in order to maximize the cross-sectional areaof a proximal portion of the tetherable guide-sheath 400. It will beappreciated that when there is no separating barrier between the workinglumen 410 and the tether lumen 408 the lumens merge into a common lumen409 and the tether 104 and the working device exit through a singleproximal port, e.g., in the tether gripper 1502. Furthermore, it will beappreciated that a proximal edge of the separating barrier 517 mayinclude a tapered wall thickness to ease the distal joint 108 of theworking device as it is advanced from the common lumen 409 into theworking lumen 410 and through the mouth 508.

Referring to FIG. 16A, a sectional view of a tetherable guide-sheath isillustrated in accordance with an implementation. The availablecross-sectional area of the tetherable guide-sheath 400 may be used tomaximize the working lumen 410 and to minimize the tether lumen 408. Forexample, the body 402 of the tetherable guide-sheath 400 may surroundthe working lumen 410 defined by an inner diameter of a working lumenliner 418, and the tether lumen 408 may be defined by an inner diameterof a tether lumen liner 420. The lumen liners 418, 420 may be, forexample, non-concentric tubes that are laterally spaced and positionedadjacent to one another. In an implementation, a dimension of the tetherlumen 408 is large enough to allow a slip fit between the tether lumenliner 420 of the tetherable guide-sheath 400 and the runner tube 113 ofthe tethering device 100. The dimension, however, may not be largeenough to allow a slip fit between the tether lumen liner 420 and thepusher tube 109 of the tethering device 100. More particularly, thetether lumen 408 may be configured to advance over the tether 104 onlyafter the pusher tube 109 has been removed. Accordingly, cross-sectionalarea that would otherwise be required to receive the runner tube 113 mayinstead be dedicated to the working lumen 410, and thus, the workinglumen 410 may be maximized within the available cross-sectional area ofthe tetherable guide-sheath 400.

The inner liners can be constructed from a low friction polymer such asPTFE (polytetrafluoroethylene) or FEP (fluorinated ethylene propylene)to provide a smooth surface for the advancement of devices through theinner lumen. An outer jacket material can provide mechanical integrityto the inner liners and can be constructed from materials such as PEBAX,thermoplastic polyurethane, polyethylene, nylon, or the like. A thirdlayer can be incorporated that can provide reinforcement between theinner liner and the outer jacket. The reinforcement layer can preventflattening or kinking of the inner lumens of the body 402 to allowunimpeded device navigation through bends in the vasculature as well asaspiration or reverse flow. The body 402 can be circumferentiallyreinforced. The reinforcement layer can be made from metal such asstainless steel, Nitinol, Nitinol braid, helical ribbon, helical wire,cut stainless steel, or the like, or stiff polymer such as PEEK. Thereinforcement layer can be a structure such as a coil or braid, ortubing that has been laser-cut or machine-cut so as to be flexible. Inanother implementation, the reinforcement layer can be a cut hypotubesuch as a Nitinol hypotube or cut rigid polymer, or the like. The outerjacket of the body 402 can be formed of increasingly softer materialstowards the distal end. For example, proximal region of the body 402 canbe formed of a material such as Nylon, a region of the body 402 distalto the proximal region of the body 402 can have a hardness of 72Dwhereas areas more distal can be increasingly more flexible and formedof materials having a hardness of 55D, 45D, 35D extending towards thedistal tip 406, which can be formed of a material having a hardness of35D, for example. The body 402 can include a hydrophilic coating.

Referring to FIG. 16B, a sectional view of a tetherable guide-sheath isillustrated in accordance with an implementation. Dimensions of thetether lumen 408 and a working lumen 410 of the tetherable guide-sheath400 may be varied in accordance with the principle described above. Moreparticularly, although the size of the tetherable guide-sheath 400 maybe changed to accommodate a particular anatomy and/or intended workingdevice, the tether lumen 408 may be sized to receive the runner tube 113of a corresponding tethering device 100 in the anchoring deliverysystem, but may not be large enough to receive the pusher tube 113 ofthe corresponding tethering device 100.

The flexibility of the body 402 can vary over its length, withincreasing flexibility towards the distal portion of the body 402. Thevariability in flexibility may be achieved in various ways. For example,the outer jacket may change in durometer and/or material at varioussections. A lower durometer outer jacket material can be used in adistal section of the guide-sheath compared to other sections of theguide-sheath. Alternately, the wall thickness of the jacket material maybe reduced, and/or the density of the reinforcement layer may be variedto increase the flexibility. For example, the pitch of the coil or braidmay be stretched out, or the cut pattern in the tubing may be varied tobe more flexible. Alternately, the reinforcement structure or thematerials may change over the length of the elongate body 402. Inanother implementation, there is a transition section between thedistal-most flexible section and the proximal section, with one or moresections of varying flexibilities between the distal-most section andthe remainder of the elongate body 402. In this implementation, thedistal-most section is about 2 cm to about 5 cm, the transition sectionis about 2 cm to about 10 cm and the proximal section takes up theremainder of the sheath length.

FIGS. 17A-17B illustrate an implementation of a distal end of atetherable guide-sheath 400 including a variable volume chamber 515. Asmentioned above, the ramped deflecting surface 710 can deflect workingdevices from the working lumen 410 out through the mouth 508 as theworking device exits the guide-sheath 400. The ramped deflecting surface710 may be formed from a flexible membrane that is able to move, forexample, toward the mouth 508 or toward an interior of the chamber 515.Thus, the ramp 710 may flex toward the chamber when a working device isbeing delivered through the mouth 508 of the working lumen 410.Similarly, after the working device is removed from the working lumen410, the ramp 710 may flex toward the mouth 508 to capture the anchor102 within the chamber 515.

As mentioned, the tetherable guide-sheath 400 may capture the anchor 102of the tethering device 100 in one of the lumens of the tetherableguide-sheath 400. The ramp 710 not only can deflect working devices asthe devices exit the tetherable guide-sheath 400, but also can deflectthe anchor 102 of the tethering device 100 as it is withdrawn into thechamber 515. As an anchor 102 of a tethering device 100 is withdrawn ina proximal direction through the tether distal port 504 into chamber515, the anchor 102 can be deflected from the expanded state towards theunexpanded state as a reaction to a relative lack of expansion of thetether distal port 504 as compared to the anchor 102 of the tetheringdevice 100 (see FIG. 17A) as the anchor 102 is withdrawn into the tetherlumen 408. More particularly, as described below, the distal tip of thetetherable guide-sheath 400 may be advanced over the tether 104 to theanchor 102 of the tethering device 100 in the anchoring vessel, and thedesign of the anchor 102 may allow the anchor 102 to collapse as thedistal tip of the tetherable guide-sheath 400 swallows the anchor 102and the anchor 102 is pulled into the distal tether lumen 708 segment.In some implementations, the tether distal port 504 can have a largediameter at the tip where the anchor 102 is withdrawn to avoidadditional friction. The retrieval of the anchor 102 of tethering device100 may therefore be a smooth interaction having a reduced likelihoodthat the anchor 102 will catch on the distal tip or fracture on an edgeof the distal tip of the tetherable guide-sheath 400. Traction can beapplied to the tether 104 simultaneously as the tetherable guide-sheath400 is advanced forward so that the tethering device 100 causes minimaltrauma to the vessel. Once the tip of the tetherable-guide sheath 400 isadvanced over guide tether 104 and reaching the anchor 102 in the ECA,the design of the tethering device 100 can allow the anchor 102 tocollapse as the distal tip of the guide-sheath 400 swallows the anchor102. In some implementations, the withdrawal of the anchor 102 can causeexpansion of deflecting surface into the working lumen 410. At the endof the procedure, such reduction in working lumen diameter 410 can beacceptable. In some implementations, an outer diameter of the tetherableguide-sheath 400 minimally increases with the capture of the anchor 102of the tethering device 100. For example, the distal region of thetetherable guide-sheath 400 can have an inner diameter of about 0.087″to 0.088″ and can be enlarged to a diameter of about 0.100″ to 0.120″although the size can vary and/or can be flared.

FIGS. 18-20 illustrate different configurations of an anchoring deliverysystem 10 having a tethering device 100 and a tetherable guide-sheath400 configured to receive a working device 802 therethrough. FIG. 18shows a tethering device 100 extending through a tether lumen 408 of atetherable guide-sheath 400 and a working device 802 extending through aworking lumen 410 of the tetherable guide-sheath 400. The anchoringdelivery system 10 may include a combination of the tethering device 100and the tetherable guide-sheath 400. For example, the anchoring deliverysystem 10 may be manufactured as a kit including at least the tetheringdevice 100 and the tetherable guide-sheath 400. The kit can include oneor more tethering devices 100 and one or more tetherable guide-sheaths400, such as a first tetherable guide-sheath 400 having a first innerdiameter and a second tetherable guide-sheath 400 having a second,larger inner diameter. In some implementations, the kit can include thetethering device 100 pre-assembled with one or more of a hypotubepositioned over the tether 104 and the anchor 102 in a low profileconfiguration within a delivery tool. It should be appreciated that thetethering device 100 can be provided separately from the tetherableguide-sheath 400 such that it can be used with another appropriatelysized commercial guiding sheath as described elsewhere herein. Thedifferent inner diameters of the tetherable guide-sheaths 400 can beused to receive different outer diameter working devices 802. In someimplementations, the working lumen 410 of a first tetherableguide-sheath 400 can have an inner diameter that is 6 F and the workinglumen 410 of a second tetherable guide-sheath 400 can have an innerdiameter that is 8 F. The 6 F has an inner diameter of 0.071″ and the 8F has an inner diameter of 0.088″. Thus, the tetherable guide-sheaths400 can receive working devices having an outer diameter that is snug tothese dimensions. It should be appreciated that the tetherableguide-sheath 400 can be OTW or RX, which will be described in moredetail below.

During use, the tethering device 100 may be physically coupled with thetetherable guide-sheath 400, e.g., by tracking the tetherableguide-sheath 400 over the tethering device 100 and/or by locking thecomponents together, as described below. When the tetherableguide-sheath 400 includes a centrally located tether distal port 504distal to the mouth 508, the tether 104 of the tethering device 100 mayextend distally from the tether distal port 504 to the deployed anchor102 along the longitudinal axis passing through the body 402 of thetetherable guide-sheath 400. Furthermore, the anchoring delivery system10 can include a working device 802, which may be packaged as part ofthe same kit or provided separately as its own kit, to be delivered to atarget anatomy. During use, the working device 802 can be trackedthrough the tetherable guide-sheath 400 to exit the tetherableguide-sheath 400 through the mouth 508, the mouth 508 optionally locatedbetween the radiopaque markers 510, into the target anatomy. The targetanatomy can bifurcate away from the anchoring anatomy. It should beappreciated that the anchoring delivery system 10 shown in FIG. 18 caninclude any of a variety of tethering devices described herein includinga tethering device 100 incorporating an anchor 102 configured to take ona higher profile configuration.

Referring to FIG. 19, a distal end of an anchoring delivery systemhaving a tethering device 100 in a tether lumen 408 of a tetherableguide-sheath 400 and a working device 802 in a working lumen 410 of thetetherable guide-sheath 400 is illustrated in accordance with animplementation. The tethering device 100 can include an anchor 102configured to be released from constraint and expanded in the anchoringanatomy at a location distal to the tetherable guide-sheath 400. Moreparticularly, the tether 104 can extend proximally from the deployedanchor 102 through the tether distal port 504 and within the tetherlumen 408 to an exit port in the tetherable guide-sheath 400. Similarly,the working device 802 being delivered to the target anatomy can passthrough the working port 506 and the working lumen 410 to a proximalexit point, e.g., at the proximal furcation 404. As shown, when thetether distal port 504 and the working port 506 are formed in a distalface 502 of the body 402, the tether 104 and the working device 802 canexit the tetherable guide-sheath 400 generally parallel to each other.The components may, however, diverge along different paths. For example,the tether 104 may extend distally into the anchoring anatomy and theworking device 802 may extend distally into the target anatomy, whichmay bifurcate away from the anchoring anatomy. It should be appreciatedthat the anchoring delivery system shown in FIG. 19 can include any of avariety of tethering devices described herein including a tetheringdevice incorporating an anchor configured to take on a higher profileconfiguration.

Referring to FIG. 20, a distal end of an anchoring delivery systemhaving a tethering device 100 and a working device 802 in a same lumenof a tetherable guide-sheath 400 is illustrated in accordance with animplementation. When the tetherable guide-sheath 400 includes a workingport 506 in the distal face 502 of the body 402 and one or more tetherentry ports 504 in the side surface of the body 402, the tetheringdevice 100 may extend laterally through the tether entry ports 504 intothe anchoring anatomy and the working device 802 to be delivered to thetarget anatomy can extend distally from the distal face 502 along alongitudinal axis of the body 402. As described above, depending uponthe tether distal port 504 through which the tether 104 is inserted, adifferent length of the tetherable guide-sheath 400 may be tracked intothe target anatomy. For example, a segment of the tetherableguide-sheath 400 distal to the tether distal port 504 holding the tether104 may be advanced into the target anatomy that bifurcates from theanchoring anatomy. Accordingly, the tether 104 and the segment of thetetherable guide-sheath 400 distal to the utilized tether distal port504 may be pressed against the carina at which the anchoring anatomy andthe target anatomy bifurcate. It should be appreciated that theanchoring delivery system shown in FIG. 20 can include any of a varietyof tethering devices described herein including a tethering deviceincorporating an anchor configured to take on a higher profileconfiguration.

As shown in FIG. 20, tetherable guide-sheath 400 can include a singlelumen in which at least one elongated structure can be received. Forexample, the tether lumen 408 and the working lumen 410 can be a samelumen running longitudinally through tetherable guide-sheath 400 fromproximal furcation 404 to tether distal port 504 and working port 506.Thus, the tether 104 may enter a same lumen of tetherable guide-sheath400 through the tether distal port 504 as the working device 802 entersthrough the working port 506, rather than being received by separatelumens of tetherable guide-sheath 400. Thus, working port 506 shown inFIG. 20 can also be the tether distal port 504.

According to some implementations, the length of the tetherableguide-sheath 400 is long enough to access the target anatomy and exitthe arterial access site with extra length outside of a patient's bodyfor adjustments. For example, the tetherable guide-sheath 400 can belong enough to access the petrous ICA from the femoral artery such thatan extra length is still available for adjustment. The tetherableguide-sheath 400 can be a variety of sizes to accept various workingdevices 802 and can be accommodated to the operator's preference. Forexample, current MAT and SMAT techniques describe delivering aspirationcatheters having inside diameters of 0.071-0.072 inches to an embolusduring AIS. Accordingly, the working lumen 410 of the tetherableguide-sheath 400 can be configured to receive such aspiration cathetersas the working device 802. For example, the working lumen 410 can havean inner diameter of at least 6 French, or preferably at least 6.3French to accommodate such working devices 802. The inner diameter ofthe tetherable guide-sheath 400, however, may be smaller or larger. Insome implementations, the working lumen 410 can have an inner diameterof 7 French or 8 French to accommodate even larger working devices 802.In some implementations, the working lumen 410 can having inner diameterof 0.088″ or 0.071″ and thus, are configured to receive a working device802 having an outer diameter that fits snug with these dimensions. Inalternative implementations, the distal tip of the tetherableguide-sheath 400 may be balloon-tipped to provide anchoring and/or flowarrest (see FIGS. 39A-39B, as will be described in more detail below).Regardless of the length and inner diameter, the tetherable guide-sheath400 is resistant to kinking during distal advancement through thevasculature.

Referring to FIG. 21, a perspective view of a tetherable guide-sheath isillustrated in accordance with an implementation. The tetherableguide-sheath 400 can be a rapid exchange (RX) type device. Accordingly,the tetherable guide-sheath 400 can include a hypotube 1102 extendingdistally from a connector 1104 at a proximal end 403. The hypotube 1102can be coupled with the body 402 of the tetherable guide-sheath 400 at ajoint between the connector 1104 and the tip 406. Furthermore, an exitport 1106 can be positioned distal from the joint. The exit port 1106can connect with the tether lumen 408 in the body 402. Furthermore, theconnector 1104 can connect with the working lumen 410 in the body 402.

Referring to FIG. 22, a sectional view, taken about line B-B of FIG. 20,of a tetherable guide-sheath is illustrated in accordance with animplementation. The body 402 of the tetherable guide-sheath 400 caninclude one or more lumens extending longitudinally toward the tip 406.For example, the body 402 can include the tether lumen 408 to receivethe tether 104 of the tethering device 100. Furthermore, the body 402can include the working lumen 410 to receive the working device 802 tobe delivered through tetherable guide-sheath 400 to a target anatomy.The lumens 408, 410 can be sized to receive their respective workingdevices in a sliding fit. For example, the tether 104 can have an outerdiameter of 0.014 inch and the tether lumen 408 can have an innerdiameter in a range of 0.015-0.020 inch sufficient to receive the outerdiameter of the tether 104. Similarly, the tether 104 can have an outerdiameter of 0.035 inch and the tether lumen 408 can have an innerdiameter in a range of 0.036-0.041 inch. The working lumen 410 may besimilarly sized according to the working device 802 that will bedelivered through it to the target anatomy. More particularly, theworking lumen 410 may have an inner diameter that is at least 0.001 inchlarger than an outer diameter of any working device 802 it is intendedto receive, particularly if the working device 802 is to be used foraspiration as will be described in more detail below.

Referring to FIG. 23, a sectional view, taken about line C-C of FIG. 20,of a tetherable guide-sheath is illustrated in accordance with animplementation. When tetherable guide-sheath 400 is an RX-type workingdevice, the hypotube 1102 may have an inner diameter that is at least aslarge as the working lumen 410 in the body 402. For example, the workinglumen 410 in the hypotube 1102 may have a diameter that is at least0.001 inch larger than any working device 802 that it is intended toreceive.

Referring to FIG. 24, a sectional view of a proximal end of the tetherlumen of a tetherable guide-sheath is illustrated in accordance with animplementation. When the tetherable guide-sheath 400 is an RX typedevice, the tether 104 of the tethering device 100 can exit the exitport 1106 in the body 402 distal to the hypotube 1102, which containsthe working lumen 410 of the tetherable guide-sheath 400. Accordingly,the exit port 1106 may be considered to be the proximal furcation 404 inthe tetherable guide-sheath 400, as it represents a location where thetether 104 and the working device 802 diverge from each other at aproximal location in the system. In practice, the exit port 1106 can belocated within the patient, and thus, the tether 104 and the hypotube1102 can emerge from the access site in a side-by-side manner. Thetether lumen 408 and the working lumen 410 can extend along respectivelongitudinal axes that are parallel to each other near the exit port1106. However, like the mouth 508 of the tetherable guide-sheath 400,the tether lumen 408 may be directed toward the exit port 1106 formed inthe side surface of the body 402 such that the tether 104 exits the body402 at an angle to the longitudinal axis of the tether lumen 408. Thisexit angle may be controlled by a radius used to form the exit port1106.

As mentioned above, the anchoring delivery systems described herein caninclude a tether gripper 1502 to fasten the tether 104 of the tetheringdevice 100 to the tetherable guide-sheath 400. FIG. 25 shows a tethergripper 1502 in accordance with an implementation. More particularly,one or more of the tethering device 100 or the tetherable guide-sheath400 can include the tether gripper 1502 at a point of fixation betweenthe components to attach the tetherable guide-sheath 400 to the tether104 of the tethering device 100. Thus, the tetherable guide-sheath 400can be reversibly attachable to the tether 104 at the point of fixation,which can be located proximal to the anchoring site at which the anchor102 of the tethering device 100 is deployed within the anchoringanatomy. Accordingly, when the anchor 102 is deployed at the anchoringsite and the tetherable guide-sheath 400 is attached to the tether 104at the point of fixation, any proximal loading applied to the tetherableguide-sheath 400 distal to the fixation point can tension the tether 104between the anchoring site and the point of fixation. Furthermore, thistension can have a straightening effect on the tetherable guide-sheath400 to increase the column strength of the tetherable guide-sheath 400and buttress the tetherable guide-sheath 400 against buckling orprolapse. Proximal loading on the tetherable guide-sheath 400 may resultfrom, e.g., delivery or advancement of the working device 802 throughthe working lumen 410 of the tetherable guide-sheath 400 toward thetarget anatomy. Thus, the support provided by fixing the tether 104 tothe tetherable guide-sheath 400 in combination with anchoring within theanatomy by the anchor 102 can prevent buckling of the tetherableguide-sheath 400 during working device 802 delivery, which can improvethe ease and success of any interventional procedure performed throughthe tetherable guide-sheath 300.

In an implementation, the tether gripper 1502 is incorporated in thetetherable guide-sheath 400. One or both of the tether proximal port 414or the working proximal port 416 can incorporate a tether gripper 1502.The tether gripper 1502 can include a clamping or clipping mechanism,such as a cleat, clamp, clip, etc., to fix the respective proximal portto a separate device passing through the port. The tether gripper 1502can also include tape or suture to fix the respective proximal port to aseparate device passing through the port. By way of example, the tetherproximal port 414 can include an RHV capable of being tightened onto therunner tube 113 of the tethering device 100 when the runner tube 113extends through the tether lumen 408 of the tetherable guide-sheath 400.As such, a fixation point may be formed between the tethering device 100and the tetherable guide-sheath 400 at the tether gripper 1502 at somepoint proximal to the tether distal port 504. Again with respect to FIG.25, the tether gripper 1502 can include a fixation mechanism having agripper body 1504 that includes the tether lumen 408 and a cap 1506 thatscrews onto the gripper body 1504 via fastening threads 1508.Furthermore, the tether gripper 1502 can include one or more seals 1510that surround the tether 104 when it is passed through the gripper body1504, and thus, prevent fluid leakage through the tether gripper 1502.It will be appreciated that the seal 1510 is illustrated here without abacking surface, but in an implementation, the tether gripper 1502 canbe designed such that the seal 1510 is squeezed when the cap 1506 isscrewed onto the gripper body 1504. The seal 1510 can squeeze the tether104 with enough force to fasten the tether 104 within the tether gripper1502. In an implementation, the tether gripper 1502 can include arotating hemostatic valve (RHV) that is configured to fix the tether 104to the tetherable guide-sheath 400 without additional clamping features.For example, the RHV can be connected to the proximal furcation 404 andcan be actuated to compress the seal 1510 that grips the tether 104.

In an implementation, the tether gripper 1502 can incorporate additionalclamping features to grip the tether 104. For example, a collet 1512component can be incorporated in the tether gripper 1502 such that thetether 104 passes through a central opening of the collet 1512 betweenthe collet 1512 teeth. When the cap 1506 is screwed onto the gripperbody 1504, a taper 1514 in the cap 1506 can press against the collet1512 teeth forcing them against the tether 104. Accordingly, the tether104 can be gripped with greater force than can be achieved using, e.g.,an elastomeric seal 1510, and the tether gripper 1502 of the tetherableguide-sheath 400 can be used to fix the tetherable guide-sheath 400 tothe tether 104.

FIG. 26 shows a further implementation of a tether gripper of atetherable guide-sheath. The tether gripper 1502 of the tetherableguide-sheath 400 can be incorporated in the proximal furcation 404 ofthe tetherable guide-sheath 400. For example, the proximal furcation 404can include a gripping feature to clamp the tether 104. For example, thetether gripper 1502 can include a slot 1516 formed through a sidewall ofthe proximal furcation 404 such that the tether 104 can be pulledlaterally outward through the proximal furcation 404. Furthermore, bypulling the tether 104 out and upward through the slot 1516 withsufficient force, the tether 104 can be wedged toward a distal portionof the slot 1516. Accordingly, the tether gripper 1502 can pinch thetether 104 and prevent movement between the tether 104 and the tethergripper 1502. More particularly, the tether gripper 1502 can fix thetether 104 to the tetherable guide-sheath 400.

In the tether gripper 1502 implementations described above with respectto FIGS. 25-26, the tether lumen 408 may extend from the tether distalport 504 at the tip 406 of the tetherable guide-sheath 400 to the tethergripper 1502 connected to or incorporated in the tetherable guide-sheath400.

As described above, the tetherable guide-sheath 400 can also be an RXtype device such that the tether 104 can exit the tetherableguide-sheath 400 through the exit port 1106 within the patient anatomyas shown in FIG. 21. Thus, the exit port 1106 may not be reachable tofix the tether 104 to the tetherable guide-sheath 400 at the exit port1106. FIG. 27 shows an implementation of a tether gripper 1502 of atethering device 100 for use with an RX type guide-sheath. The tether104 can be attached to the tetherable guide-sheath 400 proximal to theexit port 1106, e.g., using a clamp, clip, etc., to fasten the tether104 to the body 402 of the tetherable guide-sheath 400. The distancebetween the fixation point and the exit port 1106 in such a case,however, may allow the tether 104 to bend relative to the tetherableguide-sheath 400 such that the tetherable guide-sheath 400 is notadequately buttressed against buckling. Accordingly, the tether gripper1502 can be incorporated in the tether 104 to fix the tether 104 to thetetherable guide-sheath 400 within the tether lumen 408. For example,the tether gripper 1502 can be integrated in the tether 104 at alocation distal to the exit port 1106. In an implementation, the tethergripper 1502 can include an expandable structure 1518 that can expandradially within the tether lumen 408 to press against an inner surfaceof the tether lumen 408 and lock the tether 104 to the tetherableguide-sheath 400 from moving slideably within the lumen 408. Theexpandable structure 1518 can be a self-expanding structure that iscaptured by a thin tubular sheath disposed over a proximal segment ofthe tether 104. More particularly, the thin tubular sheath can beretracted to expose the expandable structure 1518 and allow it to expandagainst the tether lumen 408 surface to lock the tether 104 to thetetherable guide-sheath 400. Furthermore, the thin tubular sheath can beadvanced to capture the expandable structure 1518 and allow thetetherable guide-sheath 400 to be tracked over the tether 104 again.

The expandable structure 1518 of the tether gripper 1502 can be aninflatable member, such as a balloon, that is not self-expandableso-to-speak. More particularly, the tether 104 can have a tubularstructure along a proximal segment. The tubular structure can have aproximal end 106 in fluid communication with the tether gripper 1502.The tether gripper 1502 can be connected to a syringe for inserting aninflation fluid into the tubular structure. Thus, the inflation fluidcan be delivered into an inner volume of the expandable structure 1518located at a distal joint of the tubular structure, causing the balloonto be inflated to press against the tether lumen 408 surface. Thetubular structure can have a distal joint connected with a proximal endof a core wire. More particularly, the tether 104 can include a distalsegment having a core wire extending from the distal joint of thetubular structure to the anchor 102. Accordingly, the tethering device100 can include an anchor 102 at a distal joint 108, a core wire portionof the tether 104 extending proximally from the anchor 102, and a tethergripper 1502 portion extending proximally from the core wire portion.The tether gripper 1502 implementations described above are not intendedto be limiting, but rather, illustrate that the tether gripper 1502 canbe incorporated in one or both of the tethering device 100 or thetetherable guide-sheath 400 to fix the components of the anchoringdelivery system 10 to each other during use.

Anchoring Delivery System Methods of Use

Referring to FIG. 28, a method of using an anchoring delivery system todeliver a working device is illustrated in accordance with animplementation. FIGS. 29A-29F illustrate operations of the methodillustrated in FIG. 28. Accordingly, FIGS. 28-29 are described incombination below.

An arterial access device 1902, such as a standard transfemoral sheath,can be inserted into an arterial access point such as the femoralartery. Referring to FIG. 29A, the arterial access device 1902 is showninserted via a percutaneous puncture into the common femoral artery(CFA), such as near the groin. In alternate implementations, otheraccess points can be used such as radial artery access, brachial arteryaccess, transcervical or transcarotid access to the CCA or proximalinternal carotid artery (ICA), or any other access point. In someimplementations, arterial access device 1902 has an inside diameterrange of 3 to 10 French. For example, the transfemoral sheathillustrated in FIG. 21A can be a standard 7 French sheath size.

After inserting the arterial access device 1902, a finder tool set,which can include a guidewire (not shown), a microcatheter 1910, and/ora finder catheter 1908, can be inserted individually or in combinationinto the transfemoral sheath and advanced to an anchoring vessel 1904,e.g., an ECA, ICA, CCA, etc. For example, a guidewire can be advanced tothe distal ECA, ipsilateral to a target vessel 1906, which may be theICA, using conventional techniques known to persons having ordinaryskill in the art. For example, the guidewire can be preloaded into afinder catheter 1908 and advanced to the aortic arch (AA). In someimplementations, the finder catheter 1908 includes a hook-shaped distalsection, such as in the case of a Vertebral, Hockey Stick, VTK shape, orLIMA pre-shaped catheter or the like. A distal end of the findercatheter 1908 can be manipulated and positioned at the brachiocephalicartery or right CCA. The guidewire can then be pushed up as far aspossible to the anchoring vessel 1904, e.g., the distal ipsilateral ECA.A microcatheter 1910 can be advanced over the guidewire. Optionally, thefinder catheter 1908 can be advanced over the guidewire and themicrocatheter 1910 to an anchoring site of the anchoring vessel 1904,e.g., the ECA distal to a takeoff of the target vessel 1906. It shouldbe appreciated that the anchoring vessel can include other vessels thatthose shown and described herein. Typically, an operator will use theipsilateral ECA or ICA above the bifurcation of the CCA as this is thetarget of stiff wire placement for delivery of standard sheaths. Ananchoring artery will preferentially not be in the path to the cerebraltarget, thus, anchoring target arteries include external carotid artery(ECA) or subclavian artery (SA) to access the internal carotid artery(ICA) or common carotid artery (CCA), respectively. The choice ofipsilateral SA or ECA as the anchoring target can depend on anatomy andclinical indication. For instance, it may be more challenging forcertain anatomies to easily reach the ECA or anchoring in the SA maygive the operator guide support to access most any ICA through thegenerally non-tortuous thoracic CCA.

At operation 1802, the tethering device 100 can be delivered to theanchoring vessel 1904. For example, still referring to FIG. 29A, theguidewire can be removed from the microcatheter 1910 and the tetheringdevice 100 can be inserted into and advanced through a lumen of themicrocatheter 1910 and the finder catheter 1908 until the anchor 102 isnear the anchoring vessel 1904. As described above, the tethering device100 can include an anchor 102, such as an expandable element that cananchor and/or fix into an artery with or without scaffolding the artery,and the anchor 102 can be connected to the tether 104, which includes anelongated member. The anchor 102 is not shown in FIG. 29A, since it ishidden within a distal region of the microcatheter 1910 placed in theanchoring vessel 1904. Thus, delivery of the tethering device 100 to theanchoring vessel 1904 can include advancement of the anchor 102connected to the distal end of the tether 104 through the vasculature,and not necessarily deployment of the anchor 102 from the unexpandedstate to the expanded state. The tethering device 100 can include apusher tube, such as a hypotube, extending over the tether 104 such thata distal end of the pusher tube is positioned adjacent a proximal end ofthe anchor 102. The pusher tube can provide “pushability” to anotherwise floppy tether 104 such that the anchor 102 can be advancedthrough the microcatheter 1910. A distal end of the pusher tube 109 canabut against the anchor 102 and urge it forward through a lumen of themicrocatheter 1910. The tethering device 100 and the pusher tube 109 canbe preloaded or otherwise assembled with a delivery tool configured tomaintain the anchor 102 in a low profile configuration such that theanchor 102 can be inserted into a proximal end of the microcatheter 1910and advanced to the distal anchoring vessel 1904 through themicrocatheter 1910 lumen.

At operation 1804, the anchor 102 of the tethering device 100 can bedeployed in the anchoring vessel 1904. Referring to FIG. 29B, themicrocatheter 1910 can be retracted over the tethering device 100 tounsleeve and expose the anchor 102 of the tethering device 100. In thecase of a self-expanding anchor 102 structure (see, e.g., FIG. 2B or5J), the anchor 102 of the tethering device 100 can automatically deployinto the anchoring vessel 1904. Alternatively, in the case of aninflatable anchor 102 structure (see, e.g., FIG. 2C), the anchor 102 canbe manipulated to deploy into the anchoring vessel 1904. Moreparticularly, the anchor 102 can transition from the low profile,unexpanded state to the higher profile, expanded state to contact andanchor 102 at an anchoring site within the anchoring vessel 1904, e.g.,distal to an entrance of the target vessel 1906.

Referring to FIG. 29C, the microcatheter 1910 and/or the finder catheter1908 can be removed through the arterial access device 1902 such thatthe tethering device 100 is anchored within the anchoring vessel 1904and a proximal end of the tether 104 extends from the distal joint 108through the arterial access device 1902. In some implementations,deployment of the anchor 102 and/or the deployed anchor 102 of thetethering device 100, e.g., expansion of a cage structure or inflationof a balloon anchor, or release of a wire device, may cause endothelialinjury. Accordingly, application of tension to the tether 104 when theanchor 102 is deployed may create shear stress on the vascular tissueand/or distortion of the vascular anatomy at a location of the anchordeployment. However, minor vascular trauma in the anchoring vessel 1904may be an acceptable tradeoff to get a supportive system in place whenAIS is the clinical indication for the target vessel 1906. It is alsocomprehended that the anchoring delivery system presented herein mayalso be used where the clinical syndrome is severe and the “cost” oftrauma at an endothelial cell layer level in the anchoring vessel 1904is acceptable in the judgment of the operator to achieve a desiredoutcome in the target vessel 1906. The anchoring delivery system mayalso be used for cases with or without AIS where intracerebral access isneeded, as compared to current transfemoral systems that simply do notallow such access.

At operation 1806, the tetherable guide-sheath 400 may be advanced overthe tether 104 of the tethering device 100 to position the mouth 508 ofthe tetherable guide-sheath 400 near the entrance of the target vessel1906. The tether 104 can include a length extending outside the patient.Referring to FIG. 29D, the proximal end 106 of the tether 104 (extendingoutside the patient) can be inserted into the tether distal port 504 ofthe tetherable guide-sheath 400 at a distal end of the tether lumen 408.Thus, the tether 104 can be received in the tether lumen 408. The lengthof the tether 104 extending outside the patient can be advanced throughthe tether lumen 408 until the proximal end of the tether 104 is onceagain available outside the proximal end of the sheath 400, for exampleby extending from the tether lumen 408 through the tether proximal port414. Although the tether 104 is generally not pushable up through thevasculature without a pusher tube or some kind of delivery component,the tether 104 can have enough heft that it can be pushed through thetether lumen 408 of the sheath 400. Once the tether 104 extends out thetether proximal port of the sheath 400, the tetherable guide-sheath 400can be advanced into the patient over the tether 104. The tetheringdevice 100 between the anchor 102 and the proximal end of the tether 104can be made taut such that the tether 104 of the tethering device 100can function like a rail for advancing the tetherable guide-sheath 400up the tether 104 until the working port 506, e.g., the mouth 508, ofthe tetherable guide-sheath 400 is positioned at the entrance to thetarget vessel 1906. The entrance to the target vessel 1906 can be, forexample, a carotid bifurcation, and thus, the mouth 508 may provideaccess to the ICA. Thus, the tetherable guide-sheath 400 can bepositioned to deliver a working device 802 toward the target vessel 1906through the working lumen 410 in the proximal furcation 404 while thetether 104 of the tethering device 100 exits the tetherable guide-sheath400 through the tether lumen 408 in the proximal furcation 404.

The tether 104 can provide the route for the tetherable guide-sheath400, and the tether 104 can extend the length of the vascular path andexit near a distal end of the tetherable guide-sheath 400, e.g., throughthe tip 406 or a side of the tetherable guide-sheath 400 near the tip406, leaving the working lumen 410 of the tetherable guide-sheath 400available for petrous access. The length of the tether 104 can varydepending on the type of the tetherable guide-sheath 400. Moreparticularly, the tetherable guide-sheath 400 can be an over-the-wire(OTW) type device as described above, having an exit port at a proximalend, or a rapid exchange (RX) type device, having the exit port 1106 ata medial location between ends. Thus, in the case of an OTW tetherableguide-sheath 400, the tether 104 runs within the tether lumen 408extending the length of the tetherable guide-sheath 400. Alternatively,in the case of the RX tetherable guide-sheath 400, the tether 104 runswithin the tether lumen 408 extending from the tip 406 of the tetherableguide-sheath 400 to an exit port 1106 where the tether lumen 408terminates on the outside of the tetherable guide-sheath 400. Since thelength of the tether lumen 408 that receives the tether 104 can beshorter in an RX type than in an OTW type of tetherable guide-sheath400, the length of the tether 104 of the anchoring delivery system mayvary. In some implementations, an extension member having an elongatedbody and a distal end configured to couple with a proximal end 106 ofthe tether 104 can be attached and detached from the tether 104 to allowfor the exchange of one type of tetherable guide-sheath 400, e.g., an RXtype, for another type of tetherable guide-sheath 400, e.g., an OTWtype, while maintaining the position of the tethering device 100 in thetarget anatomy.

Advancing the tetherable guide-sheath 400 over the tether 104 of thetethering device 100 can advance the tip 406 of the tetherableguide-sheath 400 through the entrance of the target vessel 1906 into thetarget vessel 1906. The tetherable guide-sheath 400 can have a stumptip. More particularly, the working port 506 can be distal to one ormore tether entry ports 504 (see, e.g., FIGS. 12A and 13). The tether104 of the tethering device 100 can be inserted through a tether distalport 504 on the side of the tetherable guide-sheath 400 proximal to thetip 406. For example, the tether 104 can be inserted into a tetherdistal port 504 near the tip 406 such that the portion of tetherableguide-sheath 400 distal to the utilized tether distal port 504 is shortenough to be able to be advanced up the tether 104 of tethering device100 through the arteries as well as long enough such that thekeel-shaped intersection of the tetherable guide-sheath 400 and thetether 104 of the tethering device 100 exerts enough force to fix thetetherable guide-sheath 400 against the carina of the anchoringvessel/target vessel bifurcation.

In another implementation, the tether 104 of the tethering device 100 isinserted into the tether distal port 504 spaced further proximally awayfrom the working port 506 at the tip 406. Thus, a longer portion of thetetherable guide-sheath 400 can extend into the target vessel 1906. Thelength of the long tip can vary depending on which tether distal port504 the tether 104 of tethering device 100 is inserted into. That is,when the tether 104 is inserted into a more proximal tether distal port504, then the distance between the utilized tether distal port 504 andthe tip 406 of the tetherable guide-sheath 400 may be longer. In variousimplementations, the at least one tether distal port 504 is adjacent toone or more radiopaque markers 510 (e.g., a pair of radiopaque markers510 may flank the utilized tether distal port 504) to indicate thelocation of the tether distal port 504 under fluoroscopy.

At operation 1808, the tetherable guide-sheath 400 can be attached tothe tether 104 of the tethering device 100. Referring to FIG. 29E, thetether 104 can be fixed to the tetherable guide-sheath 400 at a point offixation 1912 proximal to the entrance of the target vessel 1906. Thetether 104 and the tetherable guide-sheath 400 can be fixed or lockedinto position relative to each other after the tetherable guide-sheath400 is positioned at a carotid bifurcation with the mouth 508 providingaccess to the ICA, creating a tension in the tether 104 between theanchor 102 anchored in the target vessel 1904 distal to the targetvessel 1906 takeoff and the tetherable guide-sheath 400 near thearterial access site. The tether 104 can be affixed to an outer surfaceor an inner surface of the tetherable guide-sheath 400 at the point offixation 1912. The point of fixation 1912 can be outside of the patientanatomy, or in an implementation, the point of fixation 1912 can bewithin the patient anatomy, as may be the case when the tetherableguide-sheath 400 is an RX type device and the tether gripper 1502 isincorporated along the tethering device 100 (FIG. 19). The connectionbetween the tetherable guide-sheath 400 and the tether 104 can beachieved using any of the fixation mechanisms described above, e.g., bythe tether grippers 1502 described with respect to FIGS. 25-27. Suchimplementations, however, are illustrative and not limiting. Forexample, the tether 104 of the tethering device 100 can be attached tothe tetherable guide-sheath 400 using conventional securement techniquessuch as by clamping, taping, or otherwise securing the tether 104 to thetetherable guide-sheath 400.

In an implementation, the tether 104 and the tetherable guide-sheath 400are fixed by a clamp. For example, the clamp can be secured to a tab onthe outside of the tetherable guide-sheath 400 or by other means offixation. In alternative implementations, the tether 104 and thetetherable guide-sheath 400 are fixed by a hemostat, mosquito, suture,by application of a clear dressing or tape (e.g., Tegaderm™ or Opsite™),by a wire grasping element, by a closed RHV, or similar means offixation. In additional various implementations, a non-clamping fixationtechnology can be used to avoid kink development of a mechanicalfixation. For example, the tether 104 and the tetherable guide-sheath400 can be fixed magnetically as described elsewhere herein. Inaddition, the tether 104 can be fixed within a lumen of tetherableguide-sheath 400 closer to the distal tip of tetherable guide-sheath 400using a small interlocking detent within the tetherable guide-sheath400. In an implementation, the tether gripper 1502 includes a balloonthat is inflated within the tetherable guide-sheath 400 to pin thetether 104 within the tether lumen 408 and lock the relationship of thetether 104 to the tetherable guide-sheath 400. In some implementations,the tether 104 can be designed with at least one protrusion, e.g., abulge formed around the tether 104, that engages with the tether lumen408 of the tetherable guide-sheath 400. The bulge can be configured toengage the tether lumen 408 when stationary and can deflate when pushedforward. In an implementation, the tether 104 will not stretch, or mayonly minimally stretch, when pulled on.

At operation 1810, a working device 802 can be advanced through aworking lumen 410 of the tetherable guide-sheath 400 toward the targetanatomy. As described elsewhere herein, the working devices deliveredthrough the guide sheaths described herein can vary and are not intendedto be limiting. For example, the working device 802 can include aguidewire, balloon, embolectomy device like a Stentriever or aspirationcatheter. After the tetherable guide-sheath 400 is delivered to theanchoring vessel/target vessel junction, e.g., the ECA/ICA bifurcation,angiography can be performed through the tetherable guide-sheath 400 toallow full opacification of the cerebral vasculature. Referring to FIG.29F, the operator can then deliver the working device 802 into theentrance of the target vessel 1906 and proceed with a preferred AIStreatment approach aided by the anchoring provided by the fixedtethering device 100 and tetherable guide-sheath 400, i.e., theanchoring delivery system. The support provided by the anchoringdelivery system 10 can allow some AIS approaches to be performed whenthey otherwise could not have been possible because of tortuous anatomyeither at the great vessels and/or at the intracranial vasculature thattend to result in kinking and prolapse of typical sheaths as the workingdevice is advanced distally. Moreover, the additional guide support canallow procedures to be completed more quickly and simply than routineinterventional approaches. For example, some operators prefer to use aretrievable structure technique by delivering a retrievable structurevia a balloon-tipped guide catheter or a non-balloon large bore catheterto the ICA. The support of the anchoring delivery system 10 can allowthose operators to deliver their catheter systems to the petrous carotidor to a target embolus consistently. In contrast, such delivery is achallenge with current guide catheter technology.

For operators who prefer to use SMAT where the working device 802includes a large bore catheter (e.g., Covidien Navien™ A+ IntracranialSupport Catheter, Stryker/Concentric Distal Access Catheter, PenumbraBenchmark™ 071, Penumbra Neuron™ 070, etc.) that needs to be delivered,and the largest possible catheter yields the best aspiration result, theanchoring delivery system can aid in the delivery of large cathetersduring SMAT or in any other procedure. For example, using a SMATapproach to treat an M1 occlusion (an occlusion in a main stem of middlecerebral artery) with anterior circulation AIS, the working device 802can be a large bore catheter delivered through the working lumen 410 ofthe tetherable guide-sheath 400 to an embolus 1914 in the target vessel1906. Delivery can be facilitated by the anchoring of the tetheringdevice 100 and tethering of the tetherable guide-sheath 400, whichtensions the tether 104 between the anchoring site and the point offixation 1912 as the working device 802 advances through the mouth 508into the distal target vessel 1906. Accordingly, commercially available6 French intracranial catheter families which have up to 0.072 inchinner diameters for maximum diameter and aspiration capability would becompatible with a 7 or 8 French tetherable guide-sheath 400.

In various implementations, once the working device 802, e.g., a largebore catheter, exits the mouth 508 of tetherable guide-sheath 400 and isin the ICA, the fixation of the tether 104 to the tetherableguide-sheath 400 can be relaxed. The carina formed between the workingdevice 802 and the tetherable guide-sheath 400 can be advanced againstthe carina of the anchoring vessel/target vessel junction, e.g., thecarotid bifurcation, to provide an additional point of securement at thebifurcation. This carina-to-carina cinching between the device junctionand the anatomical junction can reestablish the fixation of thetethering device 100 and the tetherable guide-sheath 400, eliminatingthe possibility of both upward motion of the system and downwardbuckling or prolapsing of the tetherable guide-sheath 400 within the CCAor brachiocephalic artery. If a subsequent device, e.g., a balloonangioplasty device or another tethering device 100, is advanced out ofthe working device 802, e.g., the large bore catheter, a reaction forcecan be created when that device meets resistance. The reaction force canact on the working device 802 and may press against the tetherableguide-sheath 400. In the present system, however, the force should notreach the area of the aortic arch where prolapse is typical in standardsystems because of the anchoring of the tethering device 100 and thefixation of the tether 104 to the tetherable guide-sheath 400 as well asthe carina-to-carina cinching. The opposite reaction force can becounteracted. For example, when a Stentriever or aspiration catheterengages an embolus lodge in a cerebral vessel, the pull on the emboluscould cause the tetherable guide-sheath 400 to ride upward in thevessel. The carina-to-carina cinching can prevent this upward motion. Inessence, the tetherable guide-sheath 400 is locked into its relativeposition in the vasculature and provides a fulcrum for advancingsubsequent devices, e.g., catheter systems and interventional devices,into the distal vessels of the neurovasculature.

In an implementation, after the AIS embolus 1914 has been successfullytreated, e.g., by aspirating and/or removing the embolus 1914, allwires, retrievable structures, and catheters can be removed from thetetherable guide-sheath 400, leaving the anchoring delivery system (thetethering device 100 and the tetherable guide-sheath 400). The fixationbetween the tethering device 100 and the tetherable guide-sheath 400 canbe removed. For example, the tether 104 can be disengaged from thetether gripper 1502. Thus, the tetherable guide-sheath 400 can beadvanced over the tether 104 to the anchor 102 deployed in the anchoringvessel 1904, e.g., the ECA. In some implementations, traction on thetether 104 can be applied to keep the tethering device 100 in positionand to minimize trauma to the anchoring vessel as the tetherableguide-sheath 400 is advanced. The tetherable guide-sheath 400 can beadvanced over the tether 104 to capture the anchor 102. That is, thetetherable guide-sheath 400 can be advanced to capture the anchor 102within the tether lumen 408. Accordingly, the anchor 102 can becollapsed towards its lower profile configuration and the anchor 102 canbe disengaged from the anchoring vessel 1904. The anchoring deliverysystem can then be retracted from the patient anatomy through thearterial access by removing tetherable guide-sheath 400 and the capturedanchor 102 from the target anatomy. In an implementation, the tetherableguide-sheath 400 can be removed from the patient, leaving the deployedtethering device 100 in place, and a separate catheter, e.g., amicrocatheter, can be advanced over the tether 104 to capture the anchor102 and retrieve the tethering device 100 from the patient.

The method described with respect to FIG. 28 is illustrative, and oneskilled in the art may extrapolate from this description other methodsof using the anchoring delivery system to effectively deliver workingdevice(s) to distal regions of tortuous and complex anatomies. Severalsuch methods are described in the implementations below.

Referring now to FIG. 30, a method of using an anchoring delivery systemto deliver a working device is illustrated in accordance with animplementation. FIGS. 31A-31D illustrate operations of the methodillustrated in FIG. 30. Accordingly, FIGS. 30-31 are described incombination below.

Referring to FIG. 31A, preparation of a patient may be similar to thatdescribed above. For example, an arterial access device 1902, such as astandard transfemoral sheath, can be inserted into an arterial accesspoint such as the femoral artery. At operation 2002, a guidewire 2102can be delivered through the arterial access device 1902 to theanchoring vessel 1904. Subsequently, at operation 2004, a catheter 2103,such as a microcatheter 1910 or a finder catheter 1908, can be deliveredover the guidewire 2102 into an anchoring vessel 1904 of a targetanatomy. In an implementation, the catheter 2103 can be preloaded withthe guidewire 2102, and thus, the guidewire 2102 and the catheter 2103can be advanced simultaneously. The guidewire 2102 can extend at leastthe length of the catheter 2103 and can be independently maneuverablewithin the catheter 2103 to lead the guidewire/catheter system to theanchoring vessel 1904. The coaxial system can be moved as a unit andeach part can be manipulated independently depending on anatomicalrequirements and operator preferences. In particular implementations, afinder catheter 1908 (not shown) can also be positioned as part of theguidewire/catheter system. Thus, a route for the tethering device 100can be established by the guidewire 2102 and one or more catheters 2103.

Referring to FIG. 31B, at operation 2006, the guidewire 2102 isexchanged for the tethering device 100. The guidewire 2102 can beremoved from a lumen of the catheter 2103 and the tethering device 100can be inserted into the catheter 2103 outside of the body 402 using aninsertion tool. Insertion tools are known, for example, to insert aretrievable structure into a patient anatomy during a SMAT procedure. Itis also possible that the tethering device 100 is already preloaded inthe catheter system and the entire catheter 2103 with the tetheringdevice 100 is inserted into the catheter 2103 instead of loading thetethering device 100 into the catheter 2103 without an outer sheath.

At operation 2008, the anchor 102 of the tethering device 100 can bedeployed in the anchoring vessel 1904, e.g., the ECA. That is, theanchor 102 can be deployed at an anchoring site in the anchoring vessel1904 distal to the entrance of the target vessel 1906. Deployment of theanchor 102 can include a standard “pin and pull” technique to keep theanchor 102 in a fixed position and prevent jumping of the device whilethe catheter 2103 is pulled back to unsleeve the anchor 102.

Referring to FIG. 31C, at operation 2010, the tetherable guide-sheath400 is advanced over the catheter 2103 to position the mouth 508 of thetetherable guide-sheath 400 near an entrance of a target vessel 1906.That is, the tetherable guide-sheath 400 may include a tether lumen 408to receive both the catheter 2103 and the tether 104 to allow thetetherable guide-sheath 400 to be tracked over an outside of thecatheter 2103. Using the tethering device 100 and the catheter 2103 assupport, the tetherable guide-sheath 400 can be advanced into the CCA upto the ECA/ICA bifurcation. Advancement of the tetherable guide-sheath400 leverages the support of the tandem tether 104 and catheter 2103combination, as well as the pulling force that the anchor 102 of thetethering device 100 provides when fully deployed in the ECA. Thetetherable guide-sheath 400 can be advanced to the ECA/ICA bifurcationand a mouth 508 of the tetherable guide-sheath 400 may be directedtowards the targeted vessel 1906, e.g., the ICA. The combination of thecatheter 2103 and the tether 104 may provide sufficient column strengthto reduce the likelihood of prolapse of the tetherable guide-sheath 400into the ascending aorta, and to direct the tetherable guide-sheath 400into the brachiocephalic as described in more detail above.

Referring to FIG. 31D, at operation 2012, the catheter 2103 can beremoved from the tetherable guide-sheath 400. The tether 104 of thetethering device 100 can allow the catheter 2103 to be removed bypulling the catheter 2103 proximally. This differs from other techniquesthat require long wires and long wire exchanges. After the catheter 2103is removed, the tetherable guide-sheath 400 can be coaxially locatedover the tethering device 100. The mouth 508 of the tetherableguide-sheath 400 can be adjusted, e.g., the tetherable guide-sheath 400may be torqued, to direct the mouth 508 toward the entrance of thetarget vessel 1906, e.g., the ICA or another target vessel 1906.

At operation 2014, the tetherable guide-sheath 400 can be attached tothe tether 104 of the tethering device 100 at a point of fixation 1912proximal to the entrance of the target vessel 1906. For example, an RHV(not shown) connected to a connector of the proximal furcation 404 ofthe tetherable guide-sheath 400 can be tightened to lock the tether 104of the tethering device 100 to the tetherable guide-sheath 400.Optionally, another securement device, e.g., a tether gripper 1502incorporated in the tetherable guide-sheath 400 and/or the tetheringdevice 100, a locking element, a clamp, or another clamping device, canbe actuated to grip the tether 104 and lock the tether 104 to thetetherable guide-sheath 400. Thus, the tetherable guide-sheath 400 canbecome tethered to the deployed anchor 102 of the tethering device 100by the tether 104.

At operation 2016, a working device 802 can be advanced through aworking lumen 410 of the tetherable guide-sheath 400. For example, alarge bore catheter can be advanced into the entrance of the targetvessel 1906 as described above. Delivery of the working device 802 cancause a reaction force to be applied to the tetherable guide-sheath 400between the anchoring site and the point of fixation 1912, and thereaction force may thus tension the tether 104 between the anchoringsite and the point of fixation 1912. Accordingly, the anchoring deliverysystem can buttress the working device 802 against back-out and/orprolapse to facilitate delivery to a distal portion of the target vessel1906. The anchoring delivery system can provide dual anchoring points,for example, at the ECA and the petrous carotid, that allows theguide-sheath to be pulled into position rather than “pushed” upstream.Further, the anchoring delivery system can allow for single operatorease of use in a rapid exchange fashion.

Referring to FIG. 32, a method of using multiple anchoring deliverysystems to gain access to a target vessel is illustrated in accordancewith an implementation. FIGS. 33A-33B illustrate operations of themethod illustrated in FIG. 32. Accordingly, FIGS. 32-33 are described incombination below.

The method of FIG. 32 can include operations similar to those describedabove. For example, at operation 3202, an anchor 102 of a firsttethering device 2202 can be deployed in a first anchoring vessel 2302.Referring to FIG. 33A, the first tethering device 2202 can be comparableto the tethering device 100 described above. Thus, the operationsleading up to and including operation 3202 can be similar to thoseleading up to and including operation 1802 of FIG. 28, or those leadingup to and including operation 2008 of FIG. 30. In an implementation, thefirst anchoring vessel 2302 is a vessel proximal to the anchoring vessel1904 used to reach a target vessel 1906. For example, the firstanchoring vessel 2302 can be an ipsilateral subclavian and can be usedas a stepping stone when an operator encounters challenging anatomiesand is unable to reach the preferred anchoring vessel 1904, e.g., theECA, with a preferred guidewire/catheter system “finder set”. In theevent that the operator cannot advance the finder set to the preferredanchoring vessel 1904, the finder set may instead be advanced into thefirst anchoring vessel 2302, where the anchor 102 of first tetheringdevice 2202 can be deployed to provide an anchor point for thetetherable guide-sheath 400.

At operation 3204, a tetherable guide-sheath 400 can be advanced over atether 104 of the first tethering device 2202 to position a mouth 508 ofthe tetherable guide-sheath 400 near an entrance of the a secondanchoring vessel 1904. Thus, the operations leading up to and includingoperation 3204 can be similar to those leading up to and includingoperation 1806 of FIG. 28, or leading up to and including operation 2010of FIG. 30.

At operation 3206, a second tethering device 2204 can be advancedthrough a working lumen 410 of the tetherable guide-sheath 400 into thesecond anchoring vessel 1904. That is, using the anchoring support ofthe first tethering device 2202 and the tetherable guide-sheath 400, thesecond tethering device 2204 can be advanced through a working lumen 410of the tetherable guide-sheath 400 into the second anchoring vessel1904, e.g., the ECA. The second tethering device 2204 can include asecond anchor 102 attached to a second distal end of a second tether104, and thus, can be similar in some or all respects to the firsttethering device 2202. That is, the first and second tethering devices2202, 2204 can be duplicates of the tethering device 100 describedabove. The second anchoring vessel 1904 can be similar to the targetvessel 1906 described above, in that the second anchoring vessel 1904can branch away from the first anchoring vessel 2302 (or vice versa)like the target vessel 1906 branches from the anchoring vessel 1904 inthe above description. At operation 3208, the second anchor 102 of thesecond tethering device 2204 can be deployed in the second anchoringvessel 1904.

Referring to FIG. 33B, the tetherable guide-sheath 400 can be relocatedto facilitate delivery of a working device 802 into a target vessel1906. At operation 3210, the tetherable guide-sheath 400 can be removedfrom the tether 104 of the first tethering device 2202. At operation3212, the tetherable guide-sheath 400 can be advanced over the secondtether 104 of the second tethering device 2204 to position the mouth 508of the tetherable guide-sheath 400 near a second entrance of a secondtarget vessel 1906. For example, the mouth 508 can be positioned towarda target ICA branching from the second anchoring vessel 1904, e.g., theECA. Thus, the tetherable guide-sheath 400 can be fixed to the secondtether 104 of the second tethering device 2204 to provide support to theworking device 802 as it is advanced into the target vessel 1906 in amanner similar to that described above. Accordingly, it is contemplatedthat one or more tethering devices 100 can be used to allow an operatorto make his or her way up to the target anatomy in an operation usingany anatomy proximal to the target anatomy as a preliminary anchoringsite to advance toward a preferred anchoring site nearer to the targetartery.

In some cases, the tetherable guide-sheath 400 may not be able toadvance to retrieve the anchor 102 of the tethering device 100. Forexample, after the anchor 102 of second tethering device 2204 isanchored in the second anchoring vessel 1904, the tetherableguide-sheath 400 may be unable to advance over the tether 104 of thefirst tethering device 2202 to capture the first anchor 102 in the firstanchoring vessel 2302. In this event, the anchor 102 of the firsttethering device 2202 can be detached, as described above, and thedetached anchor 102 can remain in the patient and the detached tether104 can be pulled out of the great vessels, aorta, and out of the accesssheath and/or the arteriotomy of the access site. Alternatively, aseparate catheter can be advanced over the tether 104 of the firsttethering device 2202 after the tetherable guide-sheath 400 is removedfrom the tether 104, and the separate catheter can capture and retrievethe anchor 102.

Referring to FIG. 34, a method of using several anchoring deliverysystems to gain access to a target vessel is illustrated in accordancewith an implementation. FIGS. 35A-35C illustrate operations of themethod illustrated in FIG. 34. Accordingly, FIGS. 34-35 are described incombination below.

In some anatomies, a “through-the-anchor” approach may be used to accessa target vessel 1906. For example, referring to FIG. 35A, a complexanatomy includes a “bovine” arch where the left CCA takes off from thebrachiocephalic artery instead of the aorta. At operation 3402, ananchor 102 of a first tethering device 2202 can be deployed in a firstanchoring vessel 2302, e.g., a brachiocephalic artery proximal to a leftCCA takeoff, branching from a source vessel, e.g., the AA. At operation3404, a tetherable guide-sheath 400 can be advanced over a tether 104 ofthe first tethering device 2202 within the source vessel to position amouth 508 of the tetherable guide-sheath 400 near a takeoff of the firstanchoring vessel 2302. For example, the mouth 508 can be locatedadjacent to the takeoff of the brachiocephalic artery from the AA. Atoperation 3406, a second tethering device 2204 can be advanced through aworking lumen 410 of the tetherable guide-sheath 400 and the deployedanchor 102 of the first tethering device 2202. For example, the anchor102 of the first tethering device 2202 can have a central lumen, as inthe case of an expandable cage, or expand in a manner that allows asecond tethering device 2204 to be advanced through or along thedeployed anchor 102 of the first tethering device 2202 toward a targetvessel 1906. At operation 3408, an anchor 102 of the second tetheringdevice 2204 can be deployed in a second anchoring vessel 1904 distal tothe first anchoring vessel 2302. Thus, the tethers 104 of the firsttethering device 2202 and the second tethering device 2204 may remainwithin the tetherable guide-sheath 400, e.g., in respective lumens or ina same lumen.

Referring to FIG. 35B, at operation 3410, the tetherable guide-sheath400 can be removed from the tether 104 of the first tethering device2202. Subsequently, at operation 3412, the tetherable guide-sheath 400can be advanced over the tether 104 of the second tethering device 2204to position the mouth 508 of the tetherable guide-sheath 400 near atarget vessel 1906. The tetherable guide-sheath 400 can be advanced upthe tether 104 of second tethering device 2204 to the anchoringvessel/target vessel junction, e.g., the carotid bifurcation. The mouth508 of the tetherable guide-sheath 400 can be positioned to face thetarget vessel 1906, e.g., the ICA.

Referring to FIG. 35C, if the target vessel 1906 cannot be reached, theCCA can be used as an anchor point for the second tethering device 2204to be deployed. Thus, the anchor 102 of the first tethering device 2202can be anchored in the brachiocephalic artery, and a working device 802,such as a large bore catheter, can be delivered through a working lumen410 of the tetherable guide-sheath 400 to traverse through the anchor102 of the first tethering device 2202.

Referring to FIG. 36, a method of deploying an anchoring delivery systemto gain access to a target vessel is illustrated in accordance with animplementation. At operation 3602, an operator can deliver a findercatheter (typically a 5 F guide or diagnostic catheter) to an anchoringvessel in a patient anatomy, e.g., an external carotid artery (ECA). Atoperation 3604, the tethering device can be advanced through the findercatheter. The tethering device 100 can have a pusher tube 109 preloadedover a runner tube 113 of the tether 104. As the tethering device 100 isadvanced, the anchor 102 can slide through the finder catheter in anunexpanded state, constrained by the finder catheter. The tetheringdevice 100 can be advanced until the anchor 102 is near a distal end ofthe finder catheter, and near an anchoring site in the anchoring vessel1904. In some implementations, the distal joint 108 of the anchor 102can move relative to the proximal joint 108 of the anchor 102, i.e., theanchoring wire can slide within the runner tube, may allow the anchor102 to be easily loaded into a sheath or a catheter by simply pushingthe anchor 102 into the sheath. More particularly, by pushing the anchor102 into the sheath using the tether 104, the push force can betransmitted through the anchor 102 to cause the anchor 102 to elongateand/or contract such that the procedure effectively “pulls” the anchor102 into the sheath, which may significantly simplify loading.

At operation 3606, the anchor 102 can be deployed at the anchoring siteby advancing the anchor 102 out of the finder catheter, or by retractingthe finder catheter over the tethering device 100 to unsleeve the anchor102. The anchor 102 can therefore self-expand to the expanded state topress against, and anchor, within the anchoring vessel 1904. In animplementation, the anchor 102 includes a closed-cell structure, andthus, the anchor 102 can remain constricted in an unexpanded diameter aslong as the anchor 102 is not full released. This may simplify therelease of the anchor 102 into the anchoring anatomy.

Still with respect to FIG. 36, at operation 3608, after the anchor 102is anchored at the anchoring site, the pusher tube 109 can be removedfrom the tether 104. More particularly, the pusher tube 109 can bepulled proximally to slide over the runner tube 113 and to be removedfrom the patient anatomy.

At operation 3610, the operator may optionally adjust the anchor 102 toachieve a predetermined degree of anchoring. For example, the anchorwire 111 can be pulled relative to the runner tube 113 to cause adesired degree of expansion of the anchor 102. It will be noted thatthis may cause the anchor 102 to expand from a first expanded state,e.g., a self-expanded state, to a second expanded state, e.g., anactuated state. Accordingly, the second expanded state may be greaterthan the first expanded state to seat the anchor 102 in the anchoringvessel 1904. The opposite can be true, and the anchor wire 102 can beadvanced relative to the runner tube 113 to reduce the degree ofexpansion from the self-expanded state to the actuated state, e.g., ifthe operator assesses that the anchor 102 is oversized for the anchoringvessel 1904 and that a reduced expansion diameter will reduce thelikelihood of vascular trauma while still achieving effective seating ofthe anchor at the anchoring site.

At operation 3612, the finder catheter can be removed from the patientanatomy with a pulling motion. In an implementation, the anchor 102provides a resistive anchoring force greater than the friction forceapplied to the tether 104 by the finder catheter, and thus, thetethering device 100 remains in place during retraction of the findercatheter.

At operation 3614, the operator can advance the tetherable guide-sheath400 over the tether 104 of the tethering device 100. For example, theanchor wire 111 can be loaded into the tether distal port 504 of thetetherable guide-sheath 400 and the tetherable guide-sheath 400 can beadvanced over the runner tube 109 through the anatomy toward the targetvessel 1904. More particularly, the tetherable guide-sheath 400 can beadvanced until the mouth 508 is positioned at a takeoff of a targetvessel 1906, e.g., an internal carotid artery (ICA) leading to atargeted embolus. The tetherable guide-sheath 400 can be torqued torotate the mouth 508 such that a working device delivered through theworking lumen will be directed into an entrance of the target vessel1906 at the anchoring vessel/target vessel junction by the deflectingsurface in the working channel of the tetherable guide-sheath 400.

At operation 3616, the tetherable guide-sheath 400 can be attached tothe tether 104 of the tethering device 100. For example, the tethergripper 1502, e.g., an RHV or another gripping technology (see“Dedicated Exit Lumen” and “Multi-headed RHV” implementations) can beused to affix the tetherable guide-sheath 400 to the tethering device100 at a point of fixation 1912 proximal to the anchoring site 1904and/or the entrance to the target vessel 1906.

At operation 3618, the anchor wire 111 of the tether 104 can be fixed byreleasing an RHV 434 connected to the tether proximal port 414 andpulling relative to the tetherable guide-sheath 400 and then fixing itagain in position. A locking element 130 may be added to additionallyfix the anchoring wire 111 as well as given the operator an easy“handle” with which to apply push/pull on the distal anchor 102 via theanchor wire 111.

At operation 3620, a working device, e.g., a large bore catheter, may beadvanced through the working lumen into the target vessel 1906 toperform a preferred AIS treatment. As the working device is advancedinto the target vessel 1906, any reaction force applied by the distalanatomy may be transmitted by the working device to the tetherableguide-sheath 400 and the tethering device 100, placing the tether 104 intension between the anchoring site 1904 and the point of fixation 1912.Whereas such reaction force may ordinarily cause buckling of the workingdevice, the tetherable guide-sheath 400 may be buttressed by thetensioned tether 104, and thus, may effectively support the workingdevice to allow it to be advanced without buckling or prolapse. Once theworking device is in place, e.g., at the embolus, the preferred AIStreatment, e.g., aspiration of the embolus, can be performed. Theworking device can then be removed from the anchoring delivery systemand the patient anatomy.

At operation 3622, the tetherable guide-sheath 400 has a detachmentpoint 1916 that allows the operator to manually grasp the runner tube113 or apply a locking element 130 to the runner tube 113. Force may beapplied to the runner tube 113 to move the runner tube 113 relative tothe anchor wire 111 to collapse the anchor 102 from the expanded stateto or towards an unexpanded state, or from the actuated state to theself-expanded state. The anchor 102 can thus be withdrawn into thetether lumen 408 and/or chamber 515 of the tetherable guide-sheath 400,or the tetherable guide-sheath 400 can be exchanged with a separatecatheter, such as a guide or diagnostic catheter, that can be advancedover the anchor 102 to capture the anchor 102. The tetherableguide-sheath 400 and/or tethering device 100 can then be removed fromthe patient anatomy to complete the use of the anchoring delivery systemand finish the AIS intervention.

Referring to FIG. 37A, a schematic view of an anchoring delivery systemdeployed in a target anatomy is illustrated in accordance with animplementation. The proximal portion of the tetherable guide-sheath 400can incorporate a multiheaded RHV 1918. The multiheaded RHV 1918 caninclude an elongated arm 1920 having a detachment point 1916 to exposethe runner tube 113 for operator access. The elongated arm 1920 mayprovide an extension leading to the tether gripper 1502, which mayinclude an anchoring RHV. For example, the anchoring RHV may include acollet, such as a brass or metal insert in the diaphragm which allows itto grasp and hold the anchoring wire, as described in more detail above.

The detachment point 1916 can include a detachable coupling, which maybe formed by numerous mechanisms. For example, the elongated arm 1920can include an external O-ring that fits within an internal grooveformed in the multi-headed RHV. The elongated arm 1920 can include arigid or semi-rigid clear extender that is of sufficient distance toreach and surpass the end of the runner tube 113. More particularly, atransition point 1922 between the anchor wire 111 and the runner tube113, i.e., a proximal end of the runner tube 113, may occur within theelongated arm 1920 when the elongated arm 1920 is attached to themulti-headed RHV body. Accordingly, the runner tube 113 and the anchorwire 111 may be visualized, e.g., if they are of different colors orsufficient contrast to each other, in the extension tube. In animplementation, the elongated arm includes demarcations that may be usedto estimate a tension applied to the tethering device 100. For example,a first distance between a point on the anchoring wire 111 and theproximal end of the transition tube may be measured when the anchor 102is in the self-expanded state, and a second distance between thosepoints may be measured upon actuation of the anchor wire 111. Adifference in the distances may correspond to a degree of tension or anamount of anchoring provided by the tethering device 100.

The detachment point 1916 may or may not have an ability to restrain orfix the runner tube 113. In an implementation, an “in-line” RHV can beused to fix the runner tube 113 at the detachment point 1916.Alternatively, a transient fixation can be achieved using a push button,a lever, or another mechanism that can be actuated by an operator totemporarily apply pressure to the runner tube 113 when desired.Transient fixation can allow withdrawal of the anchor wire 111 relativeto the runner tube 113 for adjustments during a procedure, and suchadjustments may be followed by fixation of the anchor wire 111 with aseparate anchoring RHV. If prolonged fixation is provided on the runnertube 113 and the anchor wire 111 simultaneously, the relative size ofthe anchor 102 can remain fixed by the relative positions of the tethercomponents, and the transient increase and decrease of anchoring byloads applied to the tether 104 by the tetherable guide-sheath 400,e.g., during working device advancement, may not occur.

Reiterating the steps above with the system illustrated in FIG. 37A-37B,after the tetherable guide-sheath 400 is positioned, the tether 104 canbe fed through the elongated arm 1920 of the multiheaded RHV 1918 andthe anchoring RHV 1502 can fix the anchor wire 111 as it is tightened. Alocking element 130, i.e., a torque device as is known in the art, canalso be added to provide security of the hold on the system. If therunner tube 113 has an independent fixating technology applied to it (itis not “non-restraining”), then the relationship of the runner tube 113and the anchor wire 111 can be stabilized to fix the tension applied tothe anchor 102.

Referring to FIG. 37B, a schematic view of an anchoring delivery systemdeployed in a target anatomy is illustrated in accordance with animplementation. The proximal portion of the tetherable guide-sheath 400can include a dedicated bifurcation having the multi-headed RHV 1918.For example, the working lumen may pass through an arm of the dedicatedbifurcation having length of 10 to 20 mm between the working proximalport and the bifurcation point. Accordingly, standard RHVs may beconnected to the tetherable guide-sheath 400. This “dedicated exit”version of the tetherable guide-sheath system may include the workinglumen and the tether lumen, and the tether lumen may extend through theelongated arm and the tether gripper. More particularly, each end of thededicated bifurcation may include a “single-headed” RHV. The armsections of the dedicated bifurcation may be separated, e.g., by 10 to20 mm, to avoid operator confusion during use. The working lumen portionof the dedicated bifurcation, i.e., the working lumen and RHV connectedto the working lumen, may operate similar to typical neurovascularaccess systems. The tether lumen portion of the dedicated bifurcationmay include a clear semi-rigid or rigid segment, i.e., the elongatedarm, to allow visualization of the runner tube and anchoring wire forrefined adjustment of the expansion of the anchor, as described above.The anchor wire may also be anchored outside the locking RHV with ananchoring locking element or other clamping device. Furthermore, thedetachment point may or may not have an ability to restrain or fix therunner tube in place, as described above.

Referring to FIG. 38, a schematic view of an anchoring delivery systemdeployed in a target anatomy is illustrated in accordance with animplementation. The anchor 102 can be configured anchor within a vessel1904. As previously described, anchoring can be controlled by adjustinga relative position of the anchoring wire 111 relative to the runnertube 113. In an implementation, the tethering device 100 can include alocking mechanism to fix the relative position between the anchoringwire 111 and the runner tube 113 after the desired anchor dimension ortension is achieved.

In an implementation, the locking mechanism includes a pair of clampingmechanism or devices, such as a pair of locking elements 130. Eachlocking element 130 can have a fitting adapted to grip one or more ofthe tether components (the runner tube 113 or the anchoring wire 111)securely. Thus, a predetermined tension can be applied by gripping andmoving the tether components by a respective locking element 130. Thepair of clamping devices can be referred to as an anchor wire lockingelement 130 a (connected to the anchor wire 111) and the runner tubelocking element 130 b (connected to the runner tube 113). In animplementation, the anchor wire locking element 130 a is sized to acceptthe anchor wire 111 diameter, but not to accept the larger diameter ofthe runner tube 113. For example, the anchor wire locking element 130 acan incorporate a collet having a relaxed inner diameter smaller thanthe outer diameter of the runner tube 113. By contrast, the runner tubelocking element 130 b can be sized to receive the runner tube 113 in theunclamped state, but to lock down firmly on the runner tube 113 in alocked state, e.g., when the torque device is actuated by rotation of acap component on a body component, as is known in the art.

The paradigm of a pair of locking element devices 130 to control thetethering device anchor 102 expansion can be incorporated in a“dedicated bifurcation” version of a tetherable guide-sheath 400 or in a“multiheaded RHV” version of a tetherable guide-sheath 400. In eithercase, respective locking elements 130 can be tightened down on acorresponding anchor wire 111 and a corresponding runner tube 113 toapply tension to expand or contract the anchor 102, e.g., between anunexpanded state and an expanded state. Furthermore, the locking elementdevices 130 can be gripped to advance or withdraw the tethering device100 within the tetherable guide-sheath 400, or to advance or withdrawthe combined anchoring delivery system.

In an implementation, the locking elements 130 can be used to lock theanchor 102 in position. For example, after pulling on the anchoring wire111 relative to the runner tube 113 to expand the anchor 102, theanchoring wire locking element 130 a can be repositioned to abut aproximal end of the runner tube 113. The anchoring wire locking element130 a can then be tightened and released, such that spring forceretained within the anchor 102 can tension the anchoring wire 111 andthe proximal end of the runner tube 113 can press against (but not move)the anchoring wire locking element 130 a. The tethering device 100 cantherefore be locked into position to maintain a constant size of theexpanded anchor 102. Similarly, the runner tube locking element 130 b,after being used to apply desired pressure and expansion to the anchor102, can be loosened and advanced against the proximal furcation 404 oran RHV connected to the proximal furcation 404 so as to not allow anymotion of the runner tube 113 relative to the tetherable guide-sheath400.

Referring to FIG. 39A, a detailed sectional view, taken from Detail B ofFIG. 15A, of a distal portion of a tetherable guide-sheath isillustrated in accordance with an implementation. Many strokeinterventionists prefer the use of balloon guide catheters to createflow cessation and reduce the risk of fragmentation and distalembolization due to the constant current of antegrade flow in the Circleof Willis and internal carotid artery during Stentriever use orMAT/ADAPT/SMAT/Solumbra. Balloon guides are typically placed in thecervical ICA and single balloon inflation creates cessation of flow inthe ICA to the ICA terminus. A system is illustrated, which may be usedwith an anchoring delivery system to provide similar flow cessation.

In an implementation, a tetherable guide-sheath 400 incorporates one ormore balloons 519 near the tip to isolate the mouth from blood flowwithin a target anatomy. For example, a distal balloon 519 a and aproximal balloon 519 b positioned relative to the mouth 508 can beinflated, for example simultaneously, to transition from the state shownin FIG. 39A to the state shown in FIG. 39B. Inflation of the balloons519 of the tetherable guide-sheath 400 can be performed by delivering aninflation fluid, e.g., CO₂, contrast, contrast/saline mix, or anotherinflation fluid, through one or more inflation lumens to a respectiveballoon.

Referring to FIG. 40A, an operation of a method of deploying ananchoring delivery system deployed in a target anatomy is illustrated inaccordance with an implementation. The balloons 519 can expand to createindependent occlusive events in the anchoring vessel 1904, e.g., in aproximal portion of the ECA, and in the distal CCA, creating an effectsimilar to the ICA occlusion favored by current balloon guide usage.When in use, the tetherable guide-sheath 400 having dual balloons 519can be positioned as before with the anchoring delivery system securingthe mouth 508 to direct a working device toward the target vessel 1906,e.g., the ICA. Referring to FIG. 40B, inflation of the proximal balloon519 b and/or the distal balloon 519 a can create an occlusion at the ECAand CCA level and antegrade flow up ICA may cease. If the ECA has anearly branch point (often the superior thyroid artery or the like),there may be some “leak” from this ECA branch that will create a small,but present antegrade flow in the ICA. Care may be taken to position thedistal balloon 519 a in such a way that it occludes and covers the firstbranch of the ECA, if possible. As the ICA is a conduit vessel, it hasno branch points while it is in the cervical segment and even into thebony petrous. Near the Circle of Willis, small collateral branches tothe ICA may be present which is where the column of stagnant flow willend. It is contemplated that usage patterns of the tetherableguide-sheath may be similar with or without the balloon occlusioncapability provided by the dual balloon system, i.e., a method of usingthe anchoring delivery system may be similar to that described withrespect to FIG. 36 above, perhaps with an added operation for inflatingthe proximal balloon 519 b and/or distal balloon 519 a after advancingthe tetherable guide-sheath toward the target vessel.

Referring to FIG. 41, a flowchart of a method of deploying an anchoringdelivery system is illustrated in accordance with an implementation. Themethod shall be described below with reference to FIGS. 42A-42D, whichillustrate schematic views of an anchoring delivery system deployed in atarget anatomy, in accordance with an implementation.

At operation 4102, referring to FIG. 42A, an operator can deliver afinder catheter 1908 (typically a 5 F guide or diagnostic catheter) toan anchoring vessel in a patient anatomy, e.g., an external carotidartery (ECA). At operation 4104, the tethering device 100 can beadvanced through the finder catheter 1908. The tethering device 100 caninclude an anchor 102 having a pre-shaped element like a wire that canpass through the finder catheter as described elsewhere herein. As thetethering device 100 is advanced, the anchor 102 can slide through thefinder catheter 1908 in an unexpanded state, e.g., the lower profileconfiguration shown in FIGS. 5H-5L. The tethering device 100 can beadvanced until the anchor 102 is near a distal end of the findercatheter 1908, and near an anchoring site in the anchoring vessel 1904.The anchor 102 can be pushed through the finder catheter 1908 by thepusher tube 109.

At operation 4106, referring to FIG. 42B, the anchor 102 can be deployedat the anchoring site by advancing the anchor 102 out of the findercatheter 1908, by retracting a constraining element positioned over thetethering device 100 to unsleeve the anchor 102, or otherwise deployingthe anchor 102 at the anchoring site. The anchor 102 can thereforeself-expand, e.g., to the preformed larger profile configuration shownin FIGS. 5H-5L. In the expanded state, the anchor 102 can press against,distort, and/or anchor, within the anchoring vessel 1904. In animplementation, the anchor 102 includes a coil segment having a bulbousprofile, although the anchor 102 can also include other shapes, e.g.,pigtail, bulbous, hook-shaped, conical, etc., as described herein.

At operation 4108, after the anchor 102 is anchored at the anchoringsite, the pusher tube 109 can be removed from the tether 104. Forexample, the pusher tube 109 can be retrieved from the finder catheter1908. More particularly, the pusher tube 109 can be pulled proximally toslide over the tether 104 and to be removed from the patient anatomy.

At operation 4110, the finder catheter 1908 can be removed from thepatient anatomy with a pulling motion. In an implementation, the anchor102 can provide a resistive anchoring force greater than the frictionforce applied to the tether 104 by the finder catheter 1908, and thus,the tethering device 100 remains in place during retraction of thefinder catheter 1908.

At operation 4112, referring to FIG. 42C, the operator can advance atetherable guide-sheath 400 over the tether 104 of the tethering device100. For example, the anchor wire 111 can be loaded into a tether distalport 504 of the tetherable guide-sheath 400 and the tetherableguide-sheath 400 can be advanced over the tether 104 through the anatomytoward the target vessel 1906. More particularly, the tetherableguide-sheath 400 can be advanced until a mouth 508 is positioned at ornear a takeoff of a target vessel 1906, e.g., an internal carotid artery(ICA) leading to a targeted embolus. The tetherable guide-sheath 400 canbe torqued to rotate the mouth 508 such that a working device 802delivered through the working lumen will be directed into an entrance ofthe target vessel 1906 at the anchoring vessel/target vessel junction.It should be appreciated, however, that the mouth 508 need not bealigned with or rotated towards the entrance of the target vessel 1906for the working device 802 to be delivered into the target vessel 1906.

At operation 4114, the tetherable guide-sheath 400 can be attached tothe tether 104 of the tethering device 100. For example, a tethergripper, e.g., an RHV or another gripping technology, (not shown) can beused to affix the tetherable guide-sheath 400 to the tethering device100 at a point of fixation 1912 proximal to the anchoring site and/orthe entrance to the target vessel 1906.

At operation 4116, referring to FIG. 42D, a working device 802, e.g., alarge bore catheter, can be advanced through the working lumen into thetarget vessel 1906 to perform a preferred AIS treatment. As the workingdevice 802 is advanced into the target vessel 1906, any reaction forceapplied by the distal anatomy may be transmitted by the working device802 to the tetherable guide-sheath 400 and the tethering device 100,placing the tether 104 in tension between the anchoring site and thepoint of fixation 1912. Whereas such reaction force may ordinarily causebuckling of the working device 802, the tetherable guide-sheath 400 canbe buttressed by the tensioned tether 104, and thus, may effectivelysupport the working device 802 to allow it to be advanced withoutbuckling or prolapse. At operation 4118, once the working device 802 isin place, e.g., at an embolus, the preferred AIS treatment, e.g.,aspiration of the embolus, can be performed. The working device 802 canthen be removed from the anchoring delivery system and the patientanatomy.

At operation 4120, the tether 104 can be pulled to withdraw the anchor102 into the tether lumen 408 of the tetherable guide-sheath 400, or thetetherable guide-sheath 400 can be exchanged with a separate catheter,such as a guide or diagnostic catheter, that can be advanced over theanchor 102 to capture the anchor 102. The tetherable guide-sheath 400and/or tethering device 100 can then be removed from the patient anatomyto complete the use of the anchoring delivery system and finish the AISintervention.

Working Devices

The anchoring delivery systems described herein can be used to deliverone or more working devices through the working lumen to the distaltarget anatomy. It should be appreciated that the working devicedelivered through the anchoring delivery systems can vary. The workingdevices described herein can include a large-bore catheter, an advancedcatheter, nesting catheters, wire, or balloon. The anchoring deliverysystems described herein can be used with a variety of working devicesand reference to one particular working device is not intended to belimiting. The tension and support provided by the tethering device 100and the tetherable guide-sheath 400 allow for improved access to theparticularly tortuous anatomy of the cerebral vasculature withoutconcomitant prolapse of the tetherable guide-sheath 400 or the workingdevice being delivered when the device is advanced more distally. Theanchoring delivery systems described herein provide stability forprocedures such as AIS approaches to be performed accurately, simply andsafely in what would otherwise be prevented due to tortuosity orangulation at the great vessels and/or at the intracranial vasculature.

Again with respect to FIGS. 1A-1B, the anchoring delivery system 10 isshown as having a tethering device 100 and a tetherable guide-sheath400. As described throughout the specification, the tetherableguide-sheath 400 is configured to receive and support advancement of aworking device 802 and can be a commercially available guiding sheath.In some implementations, the working device 802 can include the rapidaspiration thrombectomy systems having a spined catheter as described,for example, in U.S. application Ser. No. 15/015,799, filed Feb. 4,2016, which is incorporated by reference herein in its entirety.

As best shown in FIG. 1B, the working device 802 can include a spinedcatheter 320 used with or without a catheter advancement element 340. Itshould be appreciated that although the spined catheter 320 is describedherein as being advanced with a catheter advancement element 340 thatother advancement tools are considered herein, such as a microcatheterand/or guidewire as are known in the art. The spined catheter 320 canhave a relatively flexible, distal luminal portion 322 coupled to a morerigid, kink-resistant proximal spine 330. The luminal portion 322 canhave an inner lumen 323 extending between a proximal end and a distalend of the luminal portion 322. The spine 330 is configured to move theluminal portion 322 in a bi-directional manner through the working lumen410 of the tetherable guide-sheath 400 such that the luminal portion 322can be advanced out of the working lumen 410 into a target location fortreatment within the target vessel. The length of the luminal portion322 can be shorter than a length of the working lumen 410 of thetetherable guide-sheath 400 such that upon advancement of the luminalportion 322 towards the target location only a short overlap region 348between the luminal portion 322 and the working lumen 410 remains, whichwill be described in more detail below.

The lumen 323 of the catheter 320 can have a first inner diameter andthe working lumen 410 of the tetherable guide-sheath 400 can have asecond, larger inner diameter. The lumens 323, 410 are configured to befluidly connected and contiguous such that fluid flow into and/or out ofthe system 10 is possible, such as by applying suction from anaspiration source coupled to the system 10 at a proximal end. Asmentioned above, the length of the luminal portion 322 is shorter than alength of the working lumen 410 of the tetherable guide-sheath 400 suchthat upon advancement of the luminal portion 322 towards the targetlocation using the spine 330 only the short overlap region 348 betweenthe luminal portion 322 and the working lumen 410 remains and thesmaller diameter spine 330 extends within the working lumen 410. Thisallows for the larger diameter working lumen 410 to maintain greateraspiration forces than would otherwise be provided by the smallerdiameter luminal portion 322 of the catheter 320. The markedly shorterlength of the luminal portion 322 results in a step up in luminaldiameter between the luminal portion 322 contiguous with the workinglumen 410 providing a markedly increased radius and luminal area foraspiration of the clot, particularly in comparison to other systemswhere the aspiration lumen runs along the entire inner diameter of theaspiration catheter. More particularly, the combined volume of theluminal area of the spined catheter 320 and the luminal area of theworking lumen 410 proximal to the distal luminal portion 322 is greaterthan the luminal area of the large bore catheter along the entire lengthof the system. Thus, the likelihood of removing the embolus in a singleaspiration attempt may be increased. More particularly, the stepped upluminal diameter along the spine 330 may enable a greater aspirationforce to be achieved resulting in improved aspiration of the embolus.Further, this configuration of the catheter 320 and spine 330 greatlyspeeds up the time required to retract and re-advance the catheter 320through the working lumen 410. The proximal spine 330 of the catheter320 has a length and structure that extends through the working lumen410 of the tetherable sheath-guide 400 to a proximal end of the system10 such that the spine 330 can be used to advance and retract thecatheter 320 through the working lumen 410. The spine 330 of thecatheter 320, however, takes up only a fraction of the luminal space ofthe system 10 resulting in increased luminal area for aspiration. Insome implementations, for example, in an OTW version of the catheter320, the spine 330 can be a hypotube having a lumen extending throughthe spine 330. The spine 330 can also be formed of a solid metal rod ora flat ribbon. In some implementations, the spine 330 is a ribbon ofstainless steel having dimensions of 0.012″×0.020″. In otherimplementations, the spine 330 can have a cross-sectional area along anarc, such as a quarter circle or a c-shape.

Generally, the outer diameter of the spine 330 is substantially smallerthan the outer diameter of the distal luminal portion 322 allowing foran increased luminal area for aspiration through the working lumen 410of the tetherable guide-sheath 400. This decreases the time it takes toaspirate the occlusion and increases the possibility of removing theocclusion in a single aspiration attempt. The stepped up luminaldiameter also increases the annular area available for forward flushingof contrast, saline, or other solutions while devices such asmicrocatheters or other devices may be coaxially positioned in theluminal portion 322 of the catheter 320 and/or the working lumen 410.This can increase the ease and ability to perform angiograms duringdevice navigation.

The outer diameter of the tetherable guide-sheath 400 can be suitablefor insertion into at least the carotid artery, with a working lumen 410suitably sized for providing a passageway for a working device 802 totreat an occlusion distal to the carotid artery towards the brain. Insome implementations, the inner diameter of the working lumen 410 can beabout 0.074″ and the outer diameter of the body of the tetherableguide-sheath 400 can be about 0.090″, corresponding to a 5 French sheathsize. In some implementations, the inner diameter of the working lumen410 can be about 0.087″ and the outer diameter of the body of thetetherable guide-sheath 400 can be about 0.104″, corresponding to a 6French sheath size. In some implementations, the inner diameter of theworking lumen 410 can be about 0.100″ and the outer diameter of the bodyof the tetherable guide-sheath 400 can be about 0.177″, corresponding toa 7 French sheath size. However, it should be appreciated that smalleror larger sheath sizes are considered herein. In some implementations,the working device has an OD configured to fit through a 6 F introducersheath (0.071″) and an inner diameter that is sized to receive a 0.054″working device. In some implementations, the working device has an ODconfigured to fit through an 8 F introducer sheath (0.088″) and an innerdiameter that is sized to receive the 0.071″ working device.

As mentioned above, the length of the body 402 and thus, the length ofthe working lumen 410 can be in the range of 80 to 90 cm or up to about100 cm or up to about 105 cm. In comparison, the length of the luminalportion 322 of the catheter 320 fed through the working lumen 410 can beshorter than the length of the body 402. In some implementations, thelength of the luminal portion 322 extends from a region near the distalend of the body 402 to a site of the occlusion, forming a proximaloverlap region 348 with the distal end. Taking into account thevariation in occlusion sites and sites where the tetherable guide-sheath400 distal tip 406 may be positioned, the length of the luminal portion322 may range from about 10 cm to about 25 cm. The length of the luminalportion 322 is less than the length of the body 402 of the tetherableguide-sheath 400 such that as the spined catheter 320 is retracted intothe working lumen 410 there remains a seal between the overlap region348 of the catheter 320 and the inner diameter of the working lumen 410.In some implementations, the length of the luminal portion 322 issufficient to reach a region of the M1 segment of the middle cerebralartery (MCA) and other major vessels from a region of the internalcarotid artery such that the proximal end region of the luminal portion322 of the catheter 320 avoids extending within the aortic arch. Thislimits the number of severe angulations the luminal portion 322 of thecatheter 320 must navigate while still reaching target sites in the moredistal cerebral anatomy. Used in conjunction with a tetherableguide-sheath 400 having a sheath body 402 and a working lumen 410, in animplementation where the spined catheter 320 reaches the ICA and thedistance to embolus can be less than 20 cm. The distal luminal portion322 having a length of approximately 25 cm can allow for an overlapregion 348 with the body 402 to create a seal. The overlap region 348can have a length of a few centimeters and may vary depending on thedistance from the embolus E to the distal end of the distal luminalportion 322, e.g., depending on how far the spined catheter 320 isadvanced relative to the guide-sheath 400.

In an implementation, the distal luminal portion 322 of the catheter 320is constructed to be flexible and lubricious, so as to be able to safelynavigate to the target location. The distal luminal portion 322 can bekink resistant and collapse resistant when subjected to high aspirationforces so as to be able to effectively aspirate a clot. The luminalportion 322 can have increasing flexibility towards the distal end withsmooth material transitions along its length to prevent any kinks,angulations or sharp bends in its structure, for example, duringnavigation of severe angulations such as those having 90° or greater to180° turns, for example at the aorto-iliac junction, the left subclaviantake-off from the aorta, the takeoff of the brachiocephalic (innominate)artery from the ascending aorta and many other peripheral locations justas in the carotid siphon. For example, a first portion of the distalluminal portion 322 can be formed of a material having a hardness of 72Dalong a first length, a second portion can be formed of a materialhaving a hardness of 55D along a second length, a third portion can beformed of a material such as Pebax MX1205 (40D) along a third length, afourth portion can be formed of a material having a hardness of 35Dalong a fourth length, a fifth portion can be formed of a materialhaving a hardness of 25D along a fifth length, a sixth portion can beformed of a material such as Tecoflex having a hardness of 85 A along asixth length, and a final distal portion of the catheter can be formedof a material such as Tecoflex having a hardness of 80 A. Thus, thedistal luminal portion 322 transition from being less flexible near itsjunction with the stainless steel spine 330 to being more flexible atthe distal-most end where the distal tip 346 of the catheter advancementelement 340 extends therefrom.

In some implementations, the distal luminal portion 322 includes two ormore layers. In some implementations, the distal luminal portion 322includes an inner lubricious liner, a reinforcement layer, and an outerjacket layer. The outer jacket layer may be composed of discreetsections of polymer with different durometers, composition, and/orthickness to vary the flexibility along the length of the distal luminalportion 322. In an implementation, the lubricious inner liner is a PTFEliner, with one or more thicknesses along variable sections offlexibility. In an implementation, the reinforcement layer is agenerally tubular structure formed of, for example, a wound ribbon orwire coil or braid. The material for the reinforcement structure may bestainless steel, for example 304 stainless steel, nitinol, cobaltchromium alloy, or other metal alloy that provides the desiredcombination of strengths, flexibility, and resistance to crush. In animplementation, the reinforcement structure includes multiple materialsand/or designs, again to vary the flexibility along the length of thedistal luminal portion 322. In an implementation, the outer surface ofthe catheter 320 is coated with a lubricious coating such as ahydrophilic coating. In some implementations the coating may be on aninner surface and/or an outer surface to reduce friction duringtracking. The coating may include a variety of materials as is known inthe art. The spine portion 330 may also be coated to improve trackingthrough the working lumen 410. Suitable lubricious polymers are wellknown in the art and may include silicone and the like, hydrophilicpolymers such as high-density polyethylene (HDPE),polytetrafluoroethylene (PTFE), polyarylene oxides,polyvinylpyrolidones, polyvinylalcohols, hydroxy alkyl cellulosics,algins, saccharides, caprolactones, and the like, and mixtures andcombinations thereof. Hydrophilic polymers may be blended amongthemselves or with formulated amounts of water insoluble compounds(including some polymers) to yield coatings with suitable lubricity,bonding, and solubility.

It is desirable to have a catheter 320 having an inner diameter that isas large as possible that can be navigated safely to the site of theocclusion, in order to optimize the aspiration force. A suitable sizefor the inner diameter of the distal luminal portion 322 may rangebetween 0.040″ and 0.100″, depending on the patient anatomy and the clotsize and composition. The outer diameter of the distal luminal portion322 can be sized for navigation into cerebral arteries, for example, atthe level of the M1 segment or M2 segment of the cerebral vessels. Theouter diameter (OD) should be as small as possible while stillmaintaining the mechanical integrity of the catheter 320. In animplementation, the difference between the OD of distal luminal portion322 of the catheter 320 and the inner diameter of the working lumen 410of the tetherable guide-sheath 400 is between 0.001″ and 0.002″. Inanother implementation, the difference is between 0.001″ and 0.004″. Insome implementations, the guide-sheath 400 ID is between 0.087″ and0.088″ and the OD of the distal luminal portion 322 of the catheter 320is approximately 0.082″ and 0.086″ such that the difference in diametersis between 0.001″ and 0.005″. In an implementation, the luminal portion322 of the catheter 320 has a uniform diameter from a proximal end to adistal end. In an implementation, the luminal portion 322 of thecatheter 320 is tapered towards the distal end of the distal luminalportion 322 such that the distal-most end of the catheter has a smallerouter diameter compared to a more proximal region of the catheter nearwhere it seals with the tetherable guide-sheath 400. In anotherimplementation, the luminal portion 322 of the catheter OD steps up atan overlap portion to more closely match the sheath inner diameter. Thisimplementation is especially useful in a system with more than onecatheter suitable for use with a single access sheath size.

The overlap region 348 can be maintained between the working lumen 410of the tetherable guide-sheath 400 near a distal end region of thesheath body 402 and the luminal portion 322 of the catheter 320 uponextension of the luminal portion 322 into the target anatomy. It shouldbe appreciated where the catheter OD of the spined catheter 320 matchesthe inner diameter of the tetherable guide-sheath 400 or the differenceis between 0.001″-0.002″, a seal to fluid being injected or aspiratedcan be achieved by the overlap region 348 such that no increase incatheter OD is necessary. The difference between the catheter OD and theinner diameter of the tetherable guide-sheath 400 can vary, for example,between 1-2 thousandths of an inch, or between 1-4 thousandths of aninch, or between 1-12 thousandths of an inch. A seal to fluid beinginjected or aspirated between the catheter and the sheath can beachieved by the overlap 348 between their substantially similardimensions without incorporating any separate sealing structure or sealfeature.

The overlap region 348 is sized and configured to create a seal thatallows for a continuous aspiration lumen from the distal tip region ofthe catheter 320 to the proximal end 403 of the tetherable guide-sheath400 where it is connected to an aspiration source. The strength of theseal achieved can be a function of the difference between the outerdiameter of the catheter 320 and the inner diameter of the working lumen410 as well as the length of the overlap region 348, the force of thesuction applied, and the materials of the components. For example, thesealing can be improved by increasing the length of the overlap region348. However, increasing the length of the overlap region 348 can resultin a greater length through which aspiration is pulled through thesmaller diameter of the luminal portion 322 rather than the largerdiameter of the working lumen 410. As another example, higher suctionforces applied by the aspiration source can create a stronger sealbetween the luminal portion 322 and the working lumen 410 even in thepresence of a shorter overlap region 348. Further, a relatively softermaterial forming the luminal portion and/or the body 402 can stillprovide a sufficient seal even if the suction forces are less and theoverlap region 348 is shorter. In an implementation, the overlap region348 is configured to enable sealing against a vacuum of up to 25 inHg,or up to 28 inHg. In an implementation, the overlap region 348 isconfigured to enable sealing against a pressure of up to 300 mmHg or upto 600 mmHg or up to 700 mmHg with minimal to no leakage.

The distal luminal portion 322 of the catheter 320 can have a radiopaquemarker 324 a at the distal tip region to aid in navigation and properpositioning of the tip under fluoroscopy (see FIG. 1B). Additionally, aproximal region of the catheter 320 may have one or more proximalradiopaque markers 324 b so that the overlap region 348 can bevisualized as the relationship between a radiopaque marker 510 on thetetherable guide-sheath 400 and the radiopaque marker 324 b on thecatheter 320. In an implementation, the two radiopaque markers (marker324 a at distal tip and a more proximal marker 324 b) are distinct so asto minimize confusion of the fluoroscopic image, for example thecatheter proximal marker 324 b may be a single band and the marker 510on the tetherable guide-sheath 400 may be a double band. The radiopaquemarkers 324 of the distal luminal portion 322, particularly those nearthe distal tip region navigating extremely tortuous anatomy, can berelatively flexible such that they do not affect the overall flexibilityof the distal luminal portion 322 near the distal tip region. Theradiopaque markers 324 can be tungsten-loaded or platinum-loaded markersthat are relatively flexible compared to other types of radiopaquemarkers used in devices where flexibility is not paramount.

As mentioned previously, the spine 330 is configured to allow distaladvancement and proximal retraction of the catheter 320 through theworking lumen 410 of the tetherable guide-sheath 400. In animplementation, the length of the spine 330 is longer than the entirelength of the tetherable guide-sheath 400 (from distal tip to proximalvalve), such as by about 5 cm to 15 cm. As shown in FIG. 1B, the spine330 can include a mark 332 to indicate the overlap between the distalluminal portion 322 of the catheter 320 and the sheath body 402. Themark 332 can be positioned so that when the mark 332 is aligned with thesheath proximal valve 434 during insertion of the catheter 320 throughthe tetherable guide-sheath 400, the spined catheter 320 is positionedat the distal-most position with the minimal overlap length needed tocreate the seal between the spined aspiration catheter 320 and theworking lumen 410.

The spine 330 can include a gripping feature such as a tab 334 on theproximal end to make the spine 330 easy to grasp and advance or retract.The tab 334 can couple with one or more other components of the systemas will be described in more detail below. The proximal tab 334 can bedesigned to be easily identifiable amongst the other devices existing inthe sheath proximal valve 434, such as guidewires or retrievable stentdevice wires. In an implementation, at least a portion of the spine 330and/or tab 334 is colored a bright color, or marked with a bright color,to make it easily distinguishable from guidewire, retrievable stenttethers, or the like. In the implementation in which multiple spinedcatheters 320 are used in a nesting fashion to reach more distallocations within the brain, each spine 330 and/or tab 334 can becolor-coded or otherwise labeled to clearly show to an operator whichspine 330 of which catheter 320 it is coupled to.

The spine 330 can be configured with sufficient stiffness to allowadvancement and retraction of the distal luminal portion 322 of thespined aspiration catheter 320, yet also be flexible enough to navigatethrough the cerebral anatomy as needed without kinking. Further, theouter diameter of the spine 330 is sized to avoid taking up too muchluminal area in the lumen 410 of the tetherable guide-sheath 400. In animplementation, the spine 330 is a round wire, with dimensions from0.014″ to 0.018″. In another implementation, the spine 330 is a ribbonwith dimensions ranging from 0.010″ to 0.015″ thick, and 0.015″ thick to0.025″ thick. The ribbon can have a variety of cross-sectional shapessuch as a flat ribbon or curved ribbon forming a c-shape or other shapealong an arc. In another implementation, the spine 330 is a hypotubeformed from a flattened ribbon of stiff material rolled into a tubularshape. In an implementation, the spine 330 material is a metal such as astainless steel or nitinol as well as a plastic such as any of a varietyof polymers.

The spine 330 can be coupled to a proximal end region of the catheter320 and/or may extend along at least a portion of the distal luminalportion 322 such that the spine 330 couples to the distal luminalportion 322 a distance away from the proximal end. The spine 330 can becoupled to the portion 322 by a variety of mechanisms including bonding,welding, gluing, sandwiching, stringing, tethering, or tying one or morecomponents making up the spine 330 and/or portion 322. In someimplementations, the spine 330 and luminal portion 322 are coupledtogether by sandwiching the spine 330 between layers of the distalluminal portion 322. For example, the spine 330 can be a hypotube or rodhaving a distal end that is skived, ground or cut such that the distalend can be laminated or otherwise attached to the layers of the catheterportion 322 near a proximal end region. The region of overlap betweenthe distal end of the spine 330 and the portion 322 can be at leastabout 1 cm. This type of coupling allows for a smooth and eventransition from the spine 330 to the luminal portion 322.

The junction between the distal luminal portion 322 of the catheter 320and the proximal spine 330 can be configured to allow a smoothtransition of flexibility between the two portions so as not to create akink or weak point, and also allow smooth passage of devices through thecontiguous inner lumen created by the working lumen 410 of thetetherable guide-sheath 400 and the lumen 323 of the luminal portion 322of the catheter 320. In an implementation, the distal luminal portion322 has a transition section 326 near where the luminal portion 322couples to the spine 330. The transition section 326 can have an angledcut such that there is no abrupt step transition from the working lumen410 of the tetherable guide-sheath 400 to the catheter 320 inner lumen323. The angled cut can be generally planer. In an alternateimplementation, the angled cut is curved or stepped to provide a moregradual transition zone. It should be appreciated that the proximal endregion of the distal luminal portion 322 can be angled in an obliquemanner relative to a longitudinal axis of the catheter 320 such that theproximal end and proximal opening into the lumen are at an angle otherthan 90° to the longitudinal axis of the catheter 320, for examplebetween approximately 0°, 5°, 10°, 15°, 20°, 25°, 30°, 35°, 40°, or 45°up to less than 90°. The proximal end region of the distal luminalportion 322 can also be aligned substantially perpendicular to thelongitudinal axis of the catheter 320 such that the proximal end andproximal opening into the lumen are substantially 90° to thelongitudinal axis of the catheter 320. Similarly, the distal end regionof the distal luminal portion 322 can be angled in an oblique mannerrelative to a longitudinal axis of the catheter 320 such that the distalend and distal opening from the lumen are at an angle other than 90° tothe longitudinal axis of the catheter 320, for example betweenapproximately 0°, 5°, 10°, 15°, 20°, 25°, 30°, 35°, 40°, or 45° up toless than 90°. The distal end region of the distal luminal portion 322can also be aligned substantially perpendicular to the longitudinal axisof the catheter 320 such that the distal end and distal opening into thelumen are substantially 90° to the longitudinal axis of the catheter320.

The distal luminal portion 322 and the spine 330 may be joined by a weldbond, a mechanical bond, an adhesive bond, or some combination thereof.The distal end of the spine 330 may have features that facilitate amechanical joint during a weld, such as a textured surface, protrudingfeatures, or cut-out features. During a heat weld process, the featureswould facilitate a mechanical bond between the polymer distal luminalportion 322 and the spine 330.

As mentioned above, an implementation of the working device 802 caninclude the spined catheter 320 supplied with a catheter advancementelement 340. The catheter advancement element 340 can include anon-expandable, flexible elongate body 360 coupled to a proximal portion366. The elongate body 360 can be received within and extended throughan internal lumen 323 of the distal luminal portion 322 of the catheter320 (see FIGS. 1A-1B). In some implementations, the distal luminalportion 322 has a single internal lumen 323 extending between proximaland distal ends. The proximal portion 366 of the catheter advancementelement 340 is coupled to a proximal end region of the elongate body 360and extends proximally therefrom. The proximal portion 366 can be lessflexible than the elongate body 360 and configured for bi-directionalmovement of the elongate body 360 of the catheter advancement element340 within the luminal portion 322 of the catheter 320, as well as formovement of the catheter system as a whole. The elongate body 360 can beinserted in a coaxial fashion through the internal lumen 323 of theluminal portion 322. The outer diameter of at least a region of theelongate body 360 can be sized to substantially fill the internal lumen323 of the luminal portion 322. The elongate body 360 can have a lengththat is at least as long as the luminal portion 322 of the catheteralthough it should be appreciated the elongate body 360 can be shorterthan the luminal portion 322 so long as at least a length remains insidethe luminal portion 322 when a distal portion of the elongate body 360is extended distal to the distal end of the luminal portion 322. Thedistal portion extending distal to the distal end of the luminal portion322 can include distal tip 346 that protrudes a length beyond the distalend of the luminal portion 322 during use of the catheter advancementelement 340. The distal tip 346 of the elongate body 360 that isconfigured to protrude distally from the distal end of the luminalportion 322 aids in the navigation of the catheter system through thetortuous anatomy of the cerebral vessels, as will be described in moredetail below. The proximal portion 366 coupled to and extendingproximally from the elongate body 360 can align generally side-by-sidewith the proximal spine 330 of the catheter 320. The arrangement betweenthe elongate body 360 and the luminal portion 322 can be maintainedduring advancement of the catheter 320 through the tortuous anatomy toreach the target location for treatment in the distal vessels and aidsin preventing the distal end of the catheter 320 from catching ontortuous branching vessels, as will be described in more detail below.

In some implementations, the elongate body 360 can have a region ofrelatively uniform outer diameter extending along at least a portion ofits length and the distal tip 346 tapers down from the uniform outerdiameter. When the catheter advancement element 340 is inserted throughthe catheter 320, this tapered distal tip 346 is configured to extendbeyond and protrude out through the distal end of the luminal portion322 whereas the more proximal region of the body 360 having a uniformdiameter remains within the luminal portion 322. As mentioned, thedistal end of the luminal portion 322 can be blunt and the distal tip346 can be tapered providing an overall elongated tapered geometry ofthe catheter system. The outer diameter of the elongate body 360 alsoapproaches the inner diameter of the luminal portion 322 such that thestep up from the elongate body 360 to the outer diameter of the luminalportion 322 is minimized and the lip formed by the distal end of theluminal portion 322 is minimized preventing the lip of the luminalportion 322 from catching on the tortuous neurovasculature, such asaround the carotid siphon near the ophthalmic artery branch. In someimplementations, the inner diameter of the luminal portion 322 can be0.072″ and the outer diameter of the elongate body 360 is 0.070″ suchthat the difference between them is only 2 thousandths of an inch. Inother implementations, the outer diameter of the elongate body 360 is0.062″. Despite this, the luminal portion 322 and the elongate body 360extending through it in co-axial fashion are flexible enough to navigatethe tortuous anatomy leading to the level of M1 or M2 arteries withoutkinking and without damaging the vessel. The length of the distal tip346 can vary. In some implementations, the length of the distal tip 346can be in a range of between about 1.5 cm and about 3.0 cm from thedistal-most terminus of the elongate body 360. In other implementations,the length of the distal tip 346 is between 2.0 cm to about 2.5 cm. Thedistal tip 346 can be a constant taper from the outer diameter of theelongate body 360 down to a second smaller outer diameter at thedistal-most tip. The constant taper of the distal tip 346 can be from0.062″ outer diameter to about 0.031″ outer diameter. The length of theconstant taper of the distal tip 346 can vary, for example, between 1 cmand 3 cm, or between 2.0 cm and 2.5 cm. It should be appreciated thatthe distal tip 346 need not taper and can achieve its soft, atraumaticand flexible characteristic due to a material property other than changein outer dimension to facilitate endovascular navigation to an embolusin tortuous anatomy. For example, the distal tip 346 can be formed of amaterial having a hardness of 35D and transitions proximally towardsincreasingly harder materials having a hardness of 55D and 72D up to theproximal portion 366, which can be a stainless steel hypotube, or acombination of a material property and tapered shape. The materials usedto form the regions of the elongate body 360 can include Pebax (such asPebax 25D, 35D, 55D, 72D) with a lubricious additive compound, such asMobilize (Compounding Solutions, Lewiston, Me.). Incorporation of alubricious additive directly into the polymer elongate body meansincorporation of a separate lubricious liner, such as a Teflon liner, isunnecessary. This allows for a more flexible element that can navigatethe distal cerebral anatomy and is less likely to kink. Similarmaterials can be used for forming the distal luminal portion 322 of thecatheter 320 providing similar advantages. It should also be appreciatedthat the flexibility of the distal tip 346 can be achieved by acombination of flexible lubricious materials and tapered shapes. Forexample, the length of the tip 346 can be kept shorter than 2-3 cm, butmaintain optimum deliverability due to a change in flexible materialfrom distal-most tip towards a more proximal region a distance away fromthe distal-most tip. In an implementation, the elongate body 360 isformed of PEBAX (polyether block amide) embedded silicone designed tomaintain the highest degree of flexibility. It should be appreciatedthat the wall thickness of the distal end of the luminal portion 322 canalso be made thin enough such that the lip formed by the distal end ofthe luminal portion 322 relative to the elongate body 360 is minimized.

As mentioned above, the elongate body 360 can be constructed to havevariable stiffness between the distal and proximal ends of the elongatebody 360. The flexibility of the elongate body 360 is highest at thedistal-most terminus of the distal tip 346 and can gradually transitionin flexibility to approach the flexibility of the distal end of theluminal portion 322. Upon coupling the catheter advancement element 340and the catheter 320, the region of the elongate body 360 extendingbeyond the distal end of the luminal portion 322 can be the mostflexible and the region of the elongate body 360 configured to bealigned with the distal end of the luminal portion 322 duringadvancement in the vessel can have a substantially identical flexibilityas the distal end of the luminal portion 322 itself. As such, theflexibility of the distal end of the luminal portion 322 and theflexibility of the body 360 just proximal to the extended portion(whether tapered or having no taper) can be substantially the same. Thisprovides a smooth transition in material properties to improve trackingof the catheter system through tortuous anatomy. Further, the moreproximal sections of the elongate body 360 can be even less flexible andincreasingly stiffer. It should be appreciated that the change inflexibility of the elongate body 360 can be a function of a materialdifference, a dimensional change such as through tapering, or acombination of the two. The elongate body 360 has a benefit over amicrocatheter in that it can have a relatively large outer diameter thatis just 0.003″-0.010″ smaller than the inner diameter of the spinedcatheter 320 and still maintain a high degree of flexibility fornavigating tortuous anatomy.

The elongate body 360 can be formed of various materials that provide asuitable flexibility and lubricity. Example materials include highdensity polyethylene, 72D PEBAX, 90D PEBAX, or equivalent stiffness andlubricity material. The flexibility of the elongate body 360 canincrease towards the distal tip such that the distal region of theelongate body 360 is softer, more flexible, and articulates and bendsmore easily than a more proximal region. For example, a more proximalregion of the elongate body can have a bending stiffness that isflexible enough to navigate tortuous anatomy such as the carotid siphonwithout kinking.

In some implementations, the elongate body 360 can be generally tubularalong at least a portion of its length such that it has a lumenextending parallel to a longitudinal axis of the catheter advancementelement 340. In an implementation, the lumen of the elongate body 360 issized to accommodate a guidewire. The guidewire can extend through thelumen from a proximal opening to a distal opening through which theguidewire can extend. In some implementations, the proximal opening isconfigured for rapid exchange rather than over-the-wire such that theproximal opening is located a distance away from a proximal tab 364 anddistal to the proximal portion 366. The lumen of the elongate body 360can be configured to receive a guidewire in the range of 0.014″ and0.018″ diameter, or in the range of between 0.014″ and 0.022″. In thisimplementation, the inner luminal diameter of the elongate body 360 canbe between 0.020″ and 0.024″. The guidewire, the catheter advancementelement 340, and the spined catheter 320 can all be assembled co-axiallyfor insertion through the working lumen 410 of the tetherableguide-sheath 400.

In other implementations, the entire catheter advancement element 340can be a tubular element configured to receive a guidewire through boththe proximal portion 366 as well as the elongate body 360. For example,the proximal portion 366 can be a hypotube or tubular element having alumen that communicates with the lumen 368 extending through theelongate body 360 (shown in FIG. 1D). In some implementations, theproximal portion 366 can be a skived hypotube of stainless steel coatedwith PTFE having an outer diameter of 0.026″. In some implementations,such as an over-the-wire version, the proximal portion 366 can be askived hypotube coupled to a proximal hub. The proximal portion 366 canextend eccentric or concentric to the distal luminal portion 322. Instill further implementations, the elongate body 360 can be a solidelement coupled to the proximal portion 366 having no guidewire lumen.At least a portion of the solid elongate body 360, such as the elongatedistal tip 346, can be formed of or embedded with or attached to amalleable material that skives down to a smaller dimension at a distalend. The distal tip 346 can be shaped to a desired angle or shapesimilar to how a guidewire may be used. The malleable length of theelongate body 360 can be at least about 1 cm, 3 cm, 5 cm, and up toabout 10 cm, 15 cm, or longer. In some implementations, the malleablelength can be about 1%, 2%, 5%, 10%, 20%, 25%, 50% or more of the totallength of the elongate body 360. The shape change can be a function of auser manually shaping the malleable length prior to insertion.Alternatively, the shape change can be a reversible and actuatable shapechange such that the tip forms the shape upon activation by a user suchthat the tip can be used in a straight format until a shape change isdesired by the user.

It should be appreciated that the elongate body 360 can extend along theentire length of the catheter 320, including the distal luminal portion322 and the spine 330 or the elongate body 360 can incorporate theproximal portion 366 that aligns generally side-by-side with the spine330 of the catheter 320, as described above. The proximal portion 366 ofthe elongate body 360 can be positioned co-axial with or eccentric tothe elongate body 360. The proximal portion 366 of the elongate body 360can have a lumen extending through it. Alternatively, the portion 366can be a solid rod or ribbon having no lumen.

Like the distal luminal portion 322 of the catheter 320, the elongatebody 360 can have one or more radiopaque markers 344 along its length.In some implementations, a distal end region can have a first radiopaquemarker 344 a and a second radiopaque marker 344 b can be located toindicate the border between the tapering of the distal tip 346 and themore proximal region of the elongate body 360 having a uniform ormaximum outer diameter. This provides a user with information regardingan optimal extension of the distal tip 346 relative to the distal end ofthe luminal portion 322 to minimize the lip at this distal end of theluminal portion 322 for advancement through tortuous anatomy. In otherimplementations, for example where the distal tip 346 is not necessarilytapered, but instead has a change in overall flexibility along itslength, the second radiopaque marker 344 b can be located to indicatethe region where the relative flexibilities of the elongate body 360 (orthe distal tip 346 of the elongate body 360) and the distal end of theluminal portion 322 are substantially the same. The marker material maybe a platinum/iridium band, a tungsten, platinum, ortantalum-impregnated polymer, or other radiopaque marker that does notimpact the flexibility of the distal tip 346 and elongate body 360. Insome implementations, the radiopaque markers are extruded Pebax loadedwith tungsten for radiopacity.

As mentioned above, the spine 330 of the catheter 320 can include aproximal tab 334 on the proximal end of the spine 330. Similarly, theproximal portion 366 coupled to the elongate body 360 can include a tab364. The tabs 334, 364 can be configured to removably and adjustableconnect to one another and/or connect to their corresponding spines. Thecoupling allows the catheter advancement element 340 to reversiblycouple with the catheter 320 to lock (and unlock) the relative extensionof the distal luminal portion 322 and the elongate body 360. This allowsthe spined catheter 320 and the catheter advancement element 340 to beadvanced as a single unit. In the locked configuration, the tab 364 canbe engaged with the catheter tab 334. In the unlocked configuration, thetab 364 may be disengaged from the catheter tab 334. The tab 364 mayattach, e.g., click or lock into, the catheter tab 334 in a fashion asto maintain the relationships of corresponding section of the elongatebody 360 and the spined catheter 320 in the locked configuration.

Such locking may be achieved by, e.g., using a detent on the tab 364that snaps into place within a recess formed in the catheter tab 334, orvice versa. For example, the tab 334 of the catheter 320 can form a ringhaving a central opening extending therethrough. The tab 364 of the body360 can have an annular detent with a central post sized to insertthrough the central opening of the tab 334 such that such that the ringof the tab 334 is received within the annular detent of tab 364 forminga singular grasping element for a user to advance and/or withdraw thecatheter system through the access sheath. The tabs 334, 364 may beaffixed or may be slideable to accommodate different relative positionsbetween the elongate body 360 and the luminal portion 322 of the spinedcatheter 320. In some implementations, a proximal end of the spine 330of the catheter 320 can include a coupling feature 335, such as clip,clamp, c-shaped element or other connector configured to receive theproximal portion 366 of the catheter advancement element 340 (see FIG.1A). The coupling feature 335 can be configured to snap together withthe proximal portion 366 through an interference fit such that a firstlevel of force is needed in order to insert the proximal portion 366into the clip of the tab 334 and a second, greater level of force isneeded to remove the proximal portion 366 from the clip of the tab 334.However, upon inserting the proximal portion 366 into the couplingfeature 335 the catheter advancement element 340 and the catheter 320can still be slideably adjusted relative to one another along alongitudinal axis of the system. The amount of force needed to slideablyadjust the relative position of the two components can be such thatinadvertent adjustment is avoided and the relative position can bemaintained during use, but can be adjusted upon conscious modification.It should be appreciated that the configuration of the coupling betweenthe proximal portion 366 of the catheter advancement element 340 and thespine 360 of the catheter 320 can vary. Generally, however, the couplingis configured to be reversible and adjustable while still providingadequate holding power between the two elements in a manner that isrelatively user-friendly (e.g. allows for one-handed use) and organizesthe proximal ends of the components (e.g. prevents the spine 360 andproximal portion 366 from becoming twisted and entangled with oneanother). It should also be appreciated that the coupling feature 335configured to prevent entanglement and aid in the organization of theproximal spines can be integrated with the tabs or can be a separatefeature located along a proximal end region of the spines.

The catheter advancement element 340 is shown in FIG. 1A in a lockedconfiguration with the catheter 320 configured for improved trackingthrough a tortuous and often diseased vasculature in acute ischemicstroke. Other configurations are considered herein. For example, theelongate body 360 can include one or more detents on an outer surface.The detents can be located near a proximal end region and/or a distalend region of the elongate body 360. The detents are configured to lockwith correspondingly-shaped surface features on the inner surface of theluminal portion 322 through which the elongate body 360 extends. Thecatheter advancement element 340 and the catheter 320 can haveincorporate more than a single point of locking connection between them.For example, a coupling feature 335, such as clip, clamp, c-shapedelement or other connector configured to hold together the catheteradvancement element 340 and spine 360 or tab of the catheter 320 asdescribed elsewhere herein.

In some implementations, the spine 330 of the spined catheter 320 canrun alongside or within a specialized channel of the proximal portion366. The channel can be located along a length of the proximal portion366 and have a cross-sectional shape that matches a cross-sectionalshape of the catheter spine 330 such that the spine 330 of the catheter320 can be received within the channel and slide smoothly along thechannel bi-directionally. Once the spined catheter 320 and elongate body360 are fixed, the combined system, i.e., the spined catheter320-catheter advancement element 340 may be delivered to a target site,for example through the working lumen 410 of the tetherable guide-sheath400 described elsewhere herein.

Anchoring Delivery System and Spined Catheter Methods of Use

As mentioned above, the luminal portion 322 has a flexibility andlubricity that when paired with the rigid spine 330 and the catheteradvancement element 340 allow for the spined catheter 320 to navigate tothe site of occlusions in the cerebral vasculature better when comparedto other systems configured to navigate the cardiac vasculature. Thesystems described herein can reach occlusions in a region of the anatomythat has a long, tortuous access route. The route may contain stenosisplaque material in the aortic arch and carotid and brachiocephalicvessel origins, presenting a risk of embolic complications. Further,cerebral vessels are usually more delicate and prone to perforation thancoronary or other peripheral vasculature. The catheter systems describedherein can provide for neurovascular interventional procedures moreeasily due to its ability to overcome these access challenges. Thecatheter systems described herein are designed for navigating tortuosityrather than pushing through it. U.S. patent application Ser. No.15/015,799, filed Feb. 4, 2016, U.S. Patent Publication Number2015/0174368, filed on Dec. 12, 2014, and U.S. Patent Publication Number2015/0173782, filed on Dec. 19, 2014, which are incorporated herein byreference, describe features of catheter devices that can navigate thetortuous anatomy of the cerebral arteries.

FIG. 43 is a method of using an anchoring delivery system 10 to delivera working device 802 that includes a spined aspiration catheter inaccordance with an implementation.

At operation 4302, a finder catheter 1908 can be delivered to ananchoring vessel 1904, e.g., an ECA, ICA, CCA, etc. in a patientanatomy. The finder catheter 1908 can be a 5 F guide catheter or adiagnostic catheter known in the art. The finder catheter 1908 can bedelivered using a guidewire such as an Amplatz or other guidewirepositioned in the ECA. At operation 4304, a tethering device 100 can beadvanced through the finder catheter 1908. The tethering device 100 canbe loaded into a dual lumen catheter having a first lumen to house thetethering device 100 and a second lumen configured to receive aguidewire and a pusher tube 109 positioned inside of the catheter toadvance the anchor 102 as described elsewhere herein. The catheterholding the tethering device 100 can be inserted through a diagnosticcatheter. As such, the 5 Fr guide or diagnostic catheter can be insertedand then a 5 Fr angiographic catheter advanced over an Amplatz or otherguidewire. The guidewire can be removed and then the tethering device100 can be advanced. The tethering device 100 is advanced and an anchor102 at a distal end of the tethering device 100 is constrained in a lowprofile, constrained configuration such that it can slide through thefinder catheter 1908. The tethering device 100 can be advanced until theanchor 102 is positioned near a distal end of the finder catheter 1908and near an anchoring site in the anchoring vessel 1904.

At operation 4306, the anchor 102 can be deployed at the anchoring siteby advancing the anchor 102 distally and/or by retracting a constrainingelement positioned over the anchor 102 of the tethering device 100 tounsleeve the anchor 102 from its constrained configuration. The anchor102 can be self-expanding, e.g., to the preformed larger profileconfiguration upon release of the constraint. In the unconstrainedstate, the anchor 102 can press against and optionally distort theanchoring vessel 1904 within which it anchors.

After the anchor 102 is anchored at the anchoring site, if a pusher tube109 was used to advance the anchor 102, the pusher tube 109 can beremoved from the tether 104 of the tethering device 100. For example,the pusher tube 109 can be retrieved from the finder catheter 1908. Moreparticularly, the pusher tube 109 can be pulled proximally to slide overthe tether 104 and to be removed from the patient anatomy.

At operation 4308, the finder catheter 1908 can be removed from thepatient anatomy with a pulling motion. In an implementation, the anchor102 can provide a resistive anchoring force greater than the frictionforce applied to the tether 104 by the finder catheter 1908, and thus,the tethering device 100 remains in place during retraction of thefinder catheter 1908.

At operation 4310, a tetherable guide-sheath 400 can be advanced overthe tether 104 of the tethering device 100. For example, an anchor wire111 can be loaded into a tether distal port 504 of the tetherableguide-sheath 400 and the tetherable guide-sheath 400 can be advancedover the tether 104 through the anatomy toward the target vessel 1906.More particularly, the tetherable guide-sheath 400 can be advanced untila mouth 508 is positioned at a takeoff of a target vessel 1906, e.g., aninternal carotid artery (ICA) leading to a targeted embolus. Thetetherable guide-sheath 400 can be torqued to rotate the mouth 508 suchthat a working device 802 delivered through the working lumen will bedirected into an entrance of the target vessel 1906 at the anchoringvessel/target vessel junction. The tetherable guide-sheath 400 can beadvanced until the mouth 508 is positioned at the desired location.

At operation 4312, the tetherable guide-sheath 400 can be attached tothe tether 104 of the tethering device 100. For example, a tethergripper, e.g., an RHV or another gripping technology, (not shown) can beused to affix the tetherable guide-sheath 400 to the tethering device100 at a point of fixation 1912 proximal to the anchoring site and/orthe entrance to the target vessel 1906. The sheath aspiration line 430can be connected to an aspiration source such as a syringe or aspirationpump. The sheath aspiration line 430 can also be connected via astopcock or stopcock manifold to a forward flush line (such as apressurized saline bag).

At operation 4314, a catheter 320 assembled co-axially with a catheteradvancement element 340 is advanced through the working lumen of thetetherable guide-sheath 400. A guidewire may be optionally advancedthrough a guidewire lumen of the catheter advancement element 340. Thespined catheter 320, the catheter advancement element 340, andoptionally the guidewire can be introduced together as a co-axialcatheter assembly 802 through the sheath proximal hemostasis valve 434.The catheter assembly 802 can be advanced through the working lumen 410of the tethered guide-sheath 400 until the catheter assembly 802 exitsthe working lumen 410 at the mouth 508. At operation 4316, the distaltip of the catheter advancement element 340 can be extended relative tothe distal end of the luminal portion of the catheter 320 until thedistal tip 346 extends distal to the blunt distal end of the luminalportion 322. At operation 4318, the relative extension between thedistal tip 346 and the distal end of the luminal portion 322 of thecatheter 320 can be maintained while the working device is advanced outfrom the mouth 508 of the tetherable guide-sheath 400 and distallytowards the embolus E in the target vessel 1906. In someimplementations, the embolus E can be located in a middle or anteriorcerebral artery and the mouth 508 of the tetherable guide-sheath 400 canbe located within the petrous segment of the ICA. As an example, thecatheter assembly 802 can be advanced beyond the mouth 508 positionedthrough the cavernous segment and the supraclinoid segment of the ICAtowards the anterior cerebral artery or middle cerebral artery. Becausethe vessels in this region of the brain follow such a tortuous path, thedistal end of the luminal portion 322 of the catheter 320 can get caughton branching vessels near severe angulation points, for example, aroundthe carotid siphon near the ophthalmic artery branch. However, asdescribed elsewhere herein the catheter advancement element 340extending through the luminal portion 322 of the catheter 320 minimizesthe lip that would otherwise be formed at the distal end of the luminalportion 322. Thus, the catheter 320 having the catheter advancementelement 340 positioned therein is less likely to hang up on these severeangulation points in the vasculature as the catheter assembly 802 isadvanced distally into the cerebral vessels. As described elsewhereherein, the flexural modulus of the material forming the distal tip ofthe catheter advancement element 340 can transition from being mostfloppy and flexible to approaching the flexural modulus of the materialforming the distal end of the catheter 320 such that the transition fromone component to the other is minimized. The transition between thedistal tip 346 of the elongate body 360 can be created due to a materialchange of this component towards the distal end of the luminal portion322. The transition can also incorporate a shape change such as thedistal taper of the distal tip 346 approaching the uniform outerdiameter of the elongate body 360 having a substantially similar outerdiameter to the luminal portion 322 of the catheter 320. The smoothtransition can also be a combination of the material change and outerdiameter change between the two components.

The catheter assembly 802 including the spined aspiration catheter 320and catheter advancement element 340 is advanced until the distal tip ispositioned at the treatment site. As the catheter assembly 802 isadvanced into the target vessel 1906, any reaction force applied by thedistal anatomy may be transmitted by the catheter assembly 802 to thetetherable guide-sheath 400 and the tethering device 100, placing thetether 104 in tension between the anchoring site and the point offixation 1912. Whereas such reaction force may ordinarily cause bucklingof the catheter assembly 802, the tetherable guide-sheath 400 can bebuttressed by the tensioned tether 104, and thus, may effectivelysupport the catheter assembly to allow it to be advanced withoutbuckling of the assembly and/or prolapse of the catheter assembly 802 orthe tetherable guide-sheath 400.

At operation 4320, the distal tip 436 is positioned at a proximal faceof the occlusion, e.g., at an embolus E, and the catheter advancementelement 340 is withdrawn from the working lumen 410 prior to performingthe preferred AIS treatment, e.g. aspiration of the embolus E, can beperformed using the catheter 320 of the catheter assembly 802. A mark332 on the spine 330 of the catheter 320 ensures that there is still anoverlap region 348 between the distal luminal portion 322 and the sheathbody 402. The catheter advancement element 340 (and the guidewire, ifpresent) can be removed from the luminal portion 322 and the workinglumen 410 of the tetherable guide-sheath 400. A forward flush can beopened to the aspiration lumen 430 to keep the lumen clear before orbetween periods of aspiration. At any point during device navigation,aspiration may be initiated from the aspiration source 600 at a levelsuitable for distal embolic protection, for example, during crossing ofthe occlusion.

Once the distal tip of the aspiration catheter 320 is positioned at aface of the embolus E, aspiration can be initiated at a level suitablefor aspiration thrombectomy, which can be higher than a level used fordistal embolic protection. The catheter 320 can remain in aspirationmode against the embolus E for some period of time, as deemed suitableby the user. The luminal portion 322 of the catheter 320 and the workinglumen 410 of the tetherable guide-sheath 400 are contiguous and form astepped up diameter for aspiration as described elsewhere herein. Theoverlap region 348 is maintained between the catheter 320 extendingdistally from the lumen 410 of the guide-sheath 400. The overlap region348 can create a seal and allow for full transmission of aspiratingforce through the contiguous lumen formed by the luminal portion 322 andthe working lumen 410 of the guide-sheath 400, as well as providing aseal for delivery of fluids to the target vessel such as angiographiccontrast injection, saline, one or more drugs, or other materialsdirectly into the neuroanatomy.

The spined aspiration catheter 320 can create a more powerful aspirationforce by allowing for the working lumen 410 of the guide-sheath 400 toprovide a majority of the aspiration column. As described elsewhereherein, the dimension of the lumen of the distal luminal portion 322 ofthe aspiration catheter 320 may be less than the diameter of the workinglumen 410 of the guide-sheath 400, which is reduced only by a diameterof the spine 330 extending therethrough. The increased diameter of thelumen 410 can create a larger aspiration column than, e.g., anaspiration column of a large bore catheter having a similar overalllength. The spined aspiration catheter 320 may also be used as asupportive delivery catheter, for example, where the operator wants toreach the petrous carotid or other hard to reach landmarks within thecerebral vasculature. More particularly, after delivering the spinedaspiration catheter 320 into the target vessel through the working lumen410 of the guide-sheath 400, a secondary working device such as aguidewire, microcatheter, stent retriever, etc. may be delivered throughthe lumen of the luminal portion 322 into a more distal anatomy toperform other procedural operations as described elsewhere herein.

Depending on the results of the aspiration thrombectomy maneuver (asobserved by flow though the aspiration line 430 and/or resistance tobackwards force on the spine 330 of the catheter 320), the user maydetermine that the embolus E has been completely aspirated, or if not,the user may choose to move the catheter 320 back and forth to aspiratethe clot in situ, or to slowly retract the catheter 320 into the mouth508 of the tetherable guide-sheath 400. If flow is restored to thetarget artery via aspiration of the clot through the catheter 320 andtetherable guide-sheath 400, a final angiogram may be performed and thecatheter 320 can be retracted. If, however, thrombus occludes thecatheter tip and cannot be removed, the catheter 320 is pulled back,with some or all of the occlusion attached through suction force to thetip of the catheter 320.

In the latter scenario, aspiration can be maintained at the tip of thecatheter 320 the entire time the catheter 320 is being pulled into thetetherable guide-sheath 400. Once the catheter 320 has been completelyretracted into the tetherable guide-sheath 400, the catheter 320 can bequickly removed from the sheath body 402 while aspiration is maintainedon the tetherable guide-sheath 400. At some time during catheterretraction, depending on if the catheter 320 is clogged with occlusivematerial, the aspiration level may be changed from a high leveldesirable for aspiration thrombectomy to a lower level desirable fordistal embolic protection. By providing the ability to maintainaspiration continuously from either the catheter tip or the sheath tipor the sheath distal region, and providing the means to changeaspiration levels and maintain aspiration, the procedure optimizes theability to aspiration clot while minimizing distal emboli and minimizingblood loss from aspiration. If desired, aspiration may also be initiatedat the flush line of the proximal valve to reduce chance of distalembolization during removal of the catheter tip with possibly adheredclot through the proximal valve.

The spined aspiration catheter 320 may be removed completely from theproximal hemostasis valve 434 of the sheath 400. Alternately, if theaccess sheath 400 has a proximal extension (not shown), the distalluminal portion 322 may be pulled into the proximal extension portionsuch that the catheter 320 and sheath 220 may be flushed to removepotential embolic material without removing the catheter 320 completelyfrom the sheath 400. A vigorous flush from the proximal valve flush linesimultaneous with aspiration from the aspiration line 430 creates aflush environment for the catheter 320 and sheath 400. If desired, acatheter clearing tool may be inserted into the sheath proximal valve434 and used at this time to clear the inner lumen of the catheter 320.If the access sheath 400 has a connector valve, the proximal portion maybe closed off from the sheath body 402 during this stage, so that thereis no risk of flushing embolic material into the sheath body 402 andthence into the artery.

Alternately, the valve may be closed off and aspiration paused while theproximal valve is opened or removed and the catheter 320 is completelyremoved from the sheath 400. Closing the valve limits the blood lossfrom the sheath 400 as the catheter 320 is removed. The catheter 320 maythen be flushed onto the table or into a bowl or other receptacle, usingthe cleaning tool. The proximal extension portion may also be flushed byproviding a flush source from the proximal valve flush line simultaneouswith aspiration from the aspiration line 430, or by opening a side porton the aspiration line 430 to flush to the table or into a bowl or otherreceptacle. If desired, an angiogram may be performed to assess flowthrough the treated artery. If the procedure dictates, the catheter 320or another catheter may be re-advanced as described above to the site ofthe occlusion to attempt another aspiration thrombectomy step. Theflushing of the catheters and proximal extension portion of the accesssheath minimizing the risk of distal emboli during these subsequentsteps.

Upon successful aspiration procedure, the anchored delivery system canbe removed. The tether 104 can be pulled to withdraw the anchor 102 intothe tether lumen 408 of the tetherable guide-sheath 400, or thetetherable guide-sheath 400 can be exchanged with a separate catheter,such as a guide or diagnostic catheter, that can be advanced over theanchor 102 to capture the anchor 102. The tetherable guide-sheath 400and/or tethering device 100 can then be removed from the patient anatomyto complete the use of the anchoring delivery system and finish the AISintervention.

As mentioned above, if after treatment of the embolus E in the firsttreatment vessel 1906 shows via angiogram that another occlusion existsdistal to the first treatment vessel, at least a second aspirationcatheter can be advanced through the lumen of the first aspirationcatheter 320 already positioned in the first treatment vessel 1906. Inthis implementation, the working device can include multiple spinedcatheters that are nested inside one another to allow for an extended ortelescoping reach into the tortuous anatomy. For example, a firstcatheter having a largest OD can be inserted through an introducersheath, such as an 8 F having an ID snug of 0.071″. The second cathetercan have an ID of 0.054″ snug to a third catheter having a correspondingOD. Each sequentially smaller catheter can extend through its respectivecatheter to reach an ever deeper location within the brain such that theoverlapping segments seal forming a contiguous lumen for aspiration thatsteps up to a larger diameter thereby maximizing aspiration force. Thecatheter having an OD configured to extend through an ID of 0.071″ canreach, for example, up to the M1 level whereas the smaller catheterhaving an OD configured to extend through an ID of 0.054″ can reach, forexample, up to the M2 level and the larger catheter having an ODconfigured to extend through an ID of 0.088″ can be used for high volumelesions, for example in the carotid terminus or basilar artery. Thesmallest catheter can serve as a clean-up device following a first passwith a 0.071″ ID. Further, aspiration through the system can be at asingle point with the RHV closed and still with single-operator use.

Referring to FIG. 44, a method of using an anchoring delivery system todeliver a working device is illustrated in accordance with animplementation. FIG. 45 illustrates an implementation of a workingdevice used in the method illustrated in FIG. 44. Accordingly, FIGS.44-45 are described in combination below.

At operation 4402, referring to FIG. 45, an access device such as atetherable guide-sheath 400 can be deployed as described elsewhereherein such that the mouth 508 is positioned at a take-off to a firsttarget vessel leading to a first target embolus. It should beappreciated, however, than any access device or guide sheath known inthe art can be used in place of a tetherable guide-sheath to perform themethod of FIG. 44 and is not intended to be limiting in this way. Atoperation 4404, a working device can be advanced through a working lumen410 of the tetherable guide-sheath 400. The working device can be afirst spined catheter 320 a having an outer diameter sized to bereceived within the working lumen 410 of the tetherable guide-sheath 400as described elsewhere herein. The first spined catheter 320 a can havea luminal portion 322 having an elongate body 360 of a catheteradvancement element 340 extending therethrough as described elsewhereherein. A distal tip 356 of the elongate body 360 can extend distal tothe luminal portion 322 to aid in the advancement of the catheter 320 athrough the vessel without hanging up on a severe angulation and/or abranching vessel. At operation 4406, the first spined catheter 320 a isadvanced through the first target vessel until the distal tip 346 islocated at a proximal face of the first target embolus. At operation4408, the first catheter advancement element (not shown) is removed fromthe luminal portion 322 of the first catheter 320 a and aspirationthrombectomy is performed on the first target embolus through the firstcatheter 320 a. An angiogram can be performed to assess the success ofaspiration thrombectomy and to identify whether a second target embolusis present (operation 4410), for example in a target vessel distal tothe first target vessel. At operation 4412, a second spined catheter 320b having a second catheter advancement element positioned therethroughcan be extended through the luminal portion 322 of the first spinedcatheter 320 b. The second spined catheter 320 b can be extended usingits proximal spine 330 b beyond a distal end of the first spinedcatheter 320 a such that the smaller diameter second spined catheter 320b can reach the second target embolus that may be located distal to thefirst target embolus and in particular within a distal vessel having anarrower dimension. In this implementation, the first spined catheter320 a can act as a support catheter for the second spined catheter 320b. The inner lumen of the second spined catheter 320 b can fluidlycommunicate with the inner lumen of the first spined catheter 320 a thatfluidly communicates with the working lumen 410 of the tetherableguide-sheath 400 forming a contiguous aspiration lumen formed of threesections of increasingly larger dimensions (operation 4414). It shouldbe appreciated that additional spined catheters 320 c can then beinserted through the luminal portion of the second spine catheter 320 band so forth. The contiguous aspiration lumens can seal against oneanother such that the appropriate pressure can be applied through thenested catheters to accomplish aspiration force sufficient foraspiration thrombectomy of distant clots. It should also be appreciatedthat each additional spined catheter can be advanced with the use of itsown catheter advancement element having appropriate corresponding outerdiameter to the inner diameter of the lumen within which it is intendedto be inserted.

The proximal end of the nested catheter system can incorporate variousgripping, organizing, and attachment features as described elsewhereherein. For example, the guide-sheath 400 can include a proximalfurcation 404 at a proximal end coupled to a rotating hemostatic valve(RHV) 434 that provides access to the working lumen 410 through whichthe components of the catheter system are inserted. Each of thecomponents of the catheter system can extend proximally out from thevalve 434. For example, spined catheters 320 a, 320 b, and 320 c nestedwithin one another can have a respective proximal spine 330 a, 330 b,and 330 c extending through the valve 434. Similarly, the proximal spine360 of the catheter advancement element 340 can also extend proximallythrough the valve 434. Each of these components in the nesting ortelescoping catheter set can incorporate identifying features at theirproximal end regions that distinguish them from one another. Forexample, each proximal spine 330 can include a tab 334 having adistinguishing shape, color, or other visual characteristic that isunique to that particular catheter 320. Further, each proximal spine 330of the nesting catheters can incorporate a coupling feature 335, such asa clip or other connector, that organizes the various spines 330 andprevents entanglement. Similarly, the proximal portion 366 of thecatheter advancement element 340 can also include a unique tab 364 thatidentifies it from the spines of the various catheters, for example, byshape, color, or other identifying feature. It should be appreciatedthat the coupling features 335 configured to prevent entanglement andaid in the organization of the proximal spines can be integrated withthe tabs or can be a separate feature located along a proximal endregion of the spines as shown in FIG. 45.

The nesting catheters and their respective catheter advancement elementscan be incorporated within a kit.

One or more components of the working devices and anchoring deliverysystems described herein may be made from a metal, metal alloy, polymer,a metal-polymer composite, ceramics, combinations thereof, and the like,or other suitable materials. Some examples of suitable metals and metalalloys include stainless steel, such as 304V, 304L, and 316LV stainlesssteel; mild steel; nickel-titanium alloy such as linear-elastic and/orsuper-elastic nitinol; other nickel alloys such asnickel-chromium-molybdenum alloys (e.g., UNS: N06625 such as INCONEL®625, UNS: N06022 such as HASTELLOY® C-22®, UNS: N10276 such asHASTELLOY® C276®, other HASTELLOY® alloys, and the like), nickel-copperalloys (e.g., UNS: N04400 such as MONEL® 400, NICKELVAC® 400, NICORROS®400, and the like), nickel-cobalt-chromium-molybdenum alloys (e.g., UNS:R30035 such as MP35-N® and the like), nickel-molybdenum alloys (e.g.,UNS: N10665 such as HASTELLOY® ALLOY B2®), other nickel-chromium alloys,other nickel-molybdenum alloys, other nickel-cobalt alloys, othernickel-iron alloys, other nickel-copper alloys, other nickel-tungsten ortungsten alloys, and the like; cobalt-chromium alloys;cobalt-chromium-molybdenum alloys (e.g., UNS: R30003 such as ELGILOY®,PHYNOX®, and the like); platinum enriched stainless steel; titanium;combinations thereof; and the like; or any other suitable material andas described elsewhere herein.

It should be appreciated that the methods described above may be adaptedto different anatomies. For example, the ipsilateral subclavian could bea point of anchoring in order to target the ipsilateral vertebralartery. Vertebral arteries are often very tortuous and benefit fromsupport to push interventional systems through them to target anatomiesat which interventions are to be performed. For example, a tetheringdevice can be positioned distal to the takeoff of the vertebral arterywith the mouth of the tetherable guide-sheath positioned at thevertebral ostium. In instances when the vertebral arteries are verytortuous, i.e., weaving in and out of the bony openings of the vertebralcolumn, the large bore catheter can provide “push” to get across theseturns, which is particularly beneficial for rapid access to the site ofAIS embolization. According to various implementations, the anchoringdelivery system may facilitate access to all four vessels of thecarotid/vertebral arterial circulation as well as anatomic variants suchas the “bovine” arch discussed above.

Implementations describe anchoring delivery systems and methods of usinganchoring delivery system to deliver working devices to targetanatomies. However, while some implementations are described withspecific regard to delivering working devices to a target vessel of aneurovascular anatomy such as a cerebral vessel, the implementations arenot so limited and certain implementations may also be applicable toother uses. For example, an anchoring delivery system as described abovemay be used to deliver working devices to a target vessel of a coronaryanatomy, to name only one possible application. It should also beappreciated that although the systems described herein are described asbeing useful for treating a particular condition or pathology, that thecondition or pathology being treated may vary and are not intended to belimiting. Use of the terms “embolus,” “embolic,” “emboli,” “thrombus,”“occlusion,” etc. that relate to a target for treatment using thedevices described herein are not intended to be limiting. The terms maybe used interchangeably and can include, but are not limited to a bloodclot, air bubble, small fatty deposit, or other object carried withinthe bloodstream to a distant site or formed at a location in a vessel.The terms may be used interchangeably herein to refer to something thatcan cause a partial or full occlusion of blood flow through or withinthe vessel.

In various implementations, description is made with reference to thefigures. However, certain implementations may be practiced without oneor more of these specific details, or in combination with other knownmethods and configurations. In the description, numerous specificdetails are set forth, such as specific configurations, dimensions, andprocesses, in order to provide a thorough understanding of theimplementations. In other instances, well-known processes andmanufacturing techniques have not been described in particular detail inorder to not unnecessarily obscure the description. Reference throughoutthis specification to “one embodiment,” “an embodiment,” “oneimplementation, “an implementation,” or the like, means that aparticular feature, structure, configuration, or characteristicdescribed is included in at least one embodiment or implementation.Thus, the appearance of the phrase “one embodiment,” “an embodiment,”“one implementation, “an implementation,” or the like, in various placesthroughout this specification are not necessarily referring to the sameembodiment or implementation. Furthermore, the particular features,structures, configurations, or characteristics may be combined in anysuitable manner in one or more implementations.

The use of relative terms throughout the description may denote arelative position or direction. For example, “distal” may indicate afirst direction away from a reference point. Similarly, “proximal” mayindicate a location in a second direction opposite to the firstdirection. However, such terms are provided to establish relative framesof reference, and are not intended to limit the use or orientation of ananchoring delivery system to a specific configuration described in thevarious implementations.

While this specification contains many specifics, these should not beconstrued as limitations on the scope of what is claimed or of what maybe claimed, but rather as descriptions of features specific toparticular embodiments. Certain features that are described in thisspecification in the context of separate embodiments can also beimplemented in combination in a single embodiment. Conversely, variousfeatures that are described in the context of a single embodiment canalso be implemented in multiple embodiments separately or in anysuitable sub-combination. Moreover, although features may be describedabove as acting in certain combinations and even initially claimed assuch, one or more features from a claimed combination can in some casesbe excised from the combination, and the claimed combination may bedirected to a sub-combination or a variation of a sub-combination.Similarly, while operations are depicted in the drawings in a particularorder, this should not be understood as requiring that such operationsbe performed in the particular order shown or in sequential order, orthat all illustrated operations be performed, to achieve desirableresults. Only a few examples and implementations are disclosed.Variations, modifications and enhancements to the described examples andimplementations and other implementations may be made based on what isdisclosed.

In the descriptions above and in the claims, phrases such as “at leastone of” or “one or more of” may occur followed by a conjunctive list ofelements or features. The term “and/or” may also occur in a list of twoor more elements or features. Unless otherwise implicitly or explicitlycontradicted by the context in which it is used, such a phrase isintended to mean any of the listed elements or features individually orany of the recited elements or features in combination with any of theother recited elements or features. For example, the phrases “at leastone of A and B;” “one or more of A and B;” and “A and/or B” are eachintended to mean “A alone, B alone, or A and B together.” A similarinterpretation is also intended for lists including three or more items.For example, the phrases “at least one of A, B, and C;” “one or more ofA, B, and C;” and “A, B, and/or C” are each intended to mean “A alone, Balone, C alone, A and B together, A and C together, B and C together, orA and B and C together.”

Use of the term “based on,” above and in the claims is intended to mean,“based at least in part on,” such that an unrecited feature or elementis also permissible.

What is claimed is:
 1. A catheter system for use to deliver a workingdevice to an intracranial artery, the catheter system comprising: atethering device comprising: an elongated tether having a distal end anda proximal end; and an anchor coupled to the distal end of the tether,the anchor deployable from a low profile configuration to a higherprofile configuration to fix the distal end of the tether at ananchoring site in an anchoring vessel; and a guide-sheath comprising: atether lumen configured to receive the tethering device, the tetherlumen communicating with a tether port near a distal end of theguide-sheath; a working lumen extending from a proximal end of the guidesheath to a mouth at or near the distal end of the guide sheath, theworking lumen configured to deliver a working device; and a deflectingsurface near the distal end of the guide sheath, the deflecting surfacelocated between the working lumen and the tether lumen, and positionedoblique to the working lumen; and a point of fixation located proximalto the anchoring site, wherein the guide-sheath is reversibly attachableto the elongated tether at the point of fixation, and wherein, when theanchor is deployed at the anchoring site and the guide-sheath isattached to the elongated tether at the point of fixation, delivery ofthe working device through the working lumen tensions the elongatedtether between the anchoring site and the point of fixation.
 2. Thecatheter system of claim 1, wherein the tether lumen is separate fromthe working lumen.
 3. The catheter system of claim 1, wherein the tetherlumen extends from the tether port to a tether gripper at the point offixation.
 4. The catheter system of claim 1, wherein the anchor in thehigher profile configuration engages an anchoring anatomy and resists aproximal pull on the tether.
 5. The catheter system of claim 1, whereinthe tether is an elongated member extending from a proximal end to adistal joint that attaches to the anchor.
 6. The catheter system ofclaim 5, wherein the distal joint removably attaches the tether to theanchor.
 7. The catheter system of claim 5, wherein the distal jointfixedly attaches the tether to the anchor.
 8. The catheter system ofclaim 1, wherein the tether has a cross-sectional diameter that variesalong a length of the tether.
 9. The catheter system of claim 1, whereinthe anchor automatically self-expands from the low profile configurationto a higher profile configuration when the anchor is unconstrained. 10.The catheter system of claim 1, wherein the anchor does notautomatically self-expand from the low profile configuration to a higherprofile configuration when the anchor is unconstrained.
 11. The cathetersystem of claim 1, wherein the tether includes an anchor wire extendingthrough a runner tube such that a withdrawal load applied to the anchorwire causes the anchor wire to move relative to the runner tube and theanchor to transition to the low profile configuration.
 12. The cathetersystem of claim 1, wherein the anchor includes several convolutedstruts.
 13. The catheter system of claim 1, wherein the anchor is acoiled wire.
 14. The catheter system of claim 1, wherein the anchor is acurved wire.
 15. The catheter system of claim 1, further comprising apusher tube slidably positioned over the tether.